Questions on Geometry: Pythagorean theorem answered by real tutors!

Algebra ->  Algebra -> Questions on Geometry: Pythagorean theorem answered by real tutors!     (Log On)
Ad: Algebra Solved!™: algebra software that solves YOUR algebra homework problems with step-by-step help!



Tutors Answer Your Questions about Pythagorean-theorem (FREE)


Question 168429: how would you find 8 square root of 3: how would you find 8 square root of 3
Answer by jim_thompson5910(9162) About Me  (Show Source):
You can put this solution on YOUR website!
Is the expression 8*sqrt(3) ???


If so, then 8*sqrt(3)=8*1.73205=13.8564


Or....


Is the expression root(3,8)???


If so, then root(3,8)=root(3,2^3)=2


Note: root(3,x^3)=x

Question 168041: The screen size of a t.V is the length of the diagonal across the screen. The height of the screen = 16inches. The diagonal of the screen is 32inches. How to i find out the width?: The screen size of a t.V is the length of the diagonal across the screen. The height of the screen = 16inches. The diagonal of the screen is 32inches. How to i find out the width?
Answer by jojo14344(809) About Me  (Show Source):
You can put this solution on YOUR website!
The highlight(D)iagonal, the highlight(H)eight, and the highlight(W)idth form a Right Triangle. And we all know in a Right riangle, the 3 sides are in a relation into equation:
hyp^2=opp^2+adj^2
where-----system(hyp=D=32inches,opp=H=16inches,adj=W=unknown)
Then:
D^2=H^2+W^2
32^2=16^2+W^2
W^2=1024-254=768
W=sqrt(768)=27.7inches, ANSWER
Thank you,
Jojo

Question 166999: A boulder 10m high is on edge of a cliff. From a point on the ground 200 ft away from the foot of the cliff, the angles of elevation of the top and bottom of the boulder are 60 degrees and 40 degrees respectively. How high is the cliff?: A boulder 10m high is on edge of a cliff. From a point on the ground 200 ft away from the foot of the cliff, the angles of elevation of the top and bottom of the boulder are 60 degrees and 40 degrees respectively. How high is the cliff?
Answer by checkley77(3380) About Me  (Show Source):
You can put this solution on YOUR website!
Using the law of tan we have the opposite/adjacent:
t(40)=x/200
.839=x/200
x=.839*200
x=167.82 meters is the height of the cliff.

Question 166528: Use the pythagorean theorem then find the exact length of the hypotenuse in the following right triangle
5 and 7
: Use the pythagorean theorem then find the exact length of the hypotenuse in the following right triangle
5 and 7

Answer by stanbon(18723) About Me  (Show Source):
You can put this solution on YOUR website!
Use the pythagorean theorem then find the exact length of the hypotenuse in the following right triangle
5 and 7
-----------------------
hypoteuse^2 = 5^2 + 7^2
h^2 = 25+49
h^2 = 74
hypotenuse = sqrt(74)
===========================
Cheers,
Stan H.

Question 164539: a radio tower located 18 miles north of a straight highway has a transmission radius of 33 miles. find x the length of the section of highway that is within the transmission radius of the tower.
: a radio tower located 18 miles north of a straight highway has a transmission radius of 33 miles. find x the length of the section of highway that is within the transmission radius of the tower.

Answer by ankor@dixie-net.com(4484) About Me  (Show Source):
You can put this solution on YOUR website!
a radio tower located 18 miles north of a straight highway has a transmission
radius of 33 miles. find x the length of the section of highway that is within
the transmission radius of the tower.
:
If you draw this out, you can see that two right triangles are formed by the
radii, the highway, and 18 mi. The radius will be the hypotenuse, the third
side will be half the distance of the highway inside the transmission circle.
:
Let a = .5x
:
a^2 + 18^2 = 33^2
:
a^2 + 324 = 1089
:
a^2 = 1089 - 324
:
a^2 = 765
:
a = sqrt(765)
a = 27.6586
:
x = 2*27.6586
:
x = 55.317 mi is the highway

Question 164371This question is from textbook Heart of Mathmatics
: Suppose you know the base of a rectangle has a length of 4 inches and a diagonal has a length of 5 inches. Find the area of the rectangle?

I'm clueless on this one. I just cant seem to get this. Any help would be greatly appreciated.
This question is from textbook Heart of Mathmatics
: Suppose you know the base of a rectangle has a length of 4 inches and a diagonal has a length of 5 inches. Find the area of the rectangle?

I'm clueless on this one. I just cant seem to get this. Any help would be greatly appreciated.

Answer by nerdybill(1039) About Me  (Show Source):
You can put this solution on YOUR website!
Because the "diagonal", "base" and "height" of the rectangle forms a "right triangle" we can apply Pythagorean's theorem.
.
Let h = height
then
h^2 + 4^2 = 5^2
h^2 + 16 = 25
h^2 = 9
h = 3 inches
.
Area is then:
"height" * "base"
= 3 * 4 = 12 square inches

Question 164365This question is from textbook
: If a right triangle has legs of length 1 and x what is the length of the hypotenuse?This question is from textbook
: If a right triangle has legs of length 1 and x what is the length of the hypotenuse?
Answer by checkley77(3380) About Me  (Show Source):
You can put this solution on YOUR website!
a^2+b^2=c^2
1^2+x^2=h^2
h=sqrt(1+x^2)

Question 164372This question is from textbook Heart of Mathmatics
: Can there be a right triangle with sides of length 1, 2 and 3? Why or why not? Can yo find a right triangle whose side lengths are consecutive natural numbers?
This question is from textbook Heart of Mathmatics
: Can there be a right triangle with sides of length 1, 2 and 3? Why or why not? Can yo find a right triangle whose side lengths are consecutive natural numbers?

Answer by checkley77(3380) About Me  (Show Source):
You can put this solution on YOUR website!
a^2+b^2=c^2
1^2+2^2=3^2
1+4=9
5=9 this says there is no right triangle with sides=1,2 & 3.
However there is a right triangle that has sides of 3 consecutive natural numbers.
3,4 & 5.
Proof:
3^2+4^2=5^2
9+16=25
25=25

Question 164280This question is from textbook
: 10^2+x^2=50^2This question is from textbook
: 10^2+x^2=50^2
Answer by Fombitz(1740) About Me  (Show Source):
You can put this solution on YOUR website!
10^2+x^2=50^2
x^2=50^2-10^2
x^2=2500-100
x^2=2400
x=0 +- sqrt(4*6*100)
x=0 +- 2*10*sqrt(6)
x=0 +- 20*sqrt(6)
If this is a length, then only use the positive value.
x=20*sqrt(6)

Question 162719: a mover must put a circular mirror two meters in diameter through a one meter by 1.8 meter doorway. find the lenght of the diagonal of the doorway. will the mirror fit?

please help:)!
: a mover must put a circular mirror two meters in diameter through a one meter by 1.8 meter doorway. find the lenght of the diagonal of the doorway. will the mirror fit?

please help:)!

Answer by checkley77(3380) About Me  (Show Source):
You can put this solution on YOUR website!
1^2+1.7^2=x^2
1+3.24=x^2
x^2=4.24
x=sqrt4.24
x=2.06 meters.
Looks like a fit.

Question 161479: Area of a sail.
The area in square meters for a triangular sail is given as
a.) Find
b.) If the height of the sail is meters, then what is the length of the base of the sail?
How would I set this up and work it?
Thank you,
Tracy
: Area of a sail.
The area in square meters for a triangular sail is given as
a.) Find
b.) If the height of the sail is meters, then what is the length of the base of the sail?
How would I set this up and work it?
Thank you,
Tracy

Answer by jim_thompson5910(9162) About Me  (Show Source):
You can put this solution on YOUR website!
You're missing some information. Please repost the entire problem (along with the given equations)

Question 161403: One side of a rectangular stage is 2 meters longer than the other. If the diagonal is 10 meters, then what are the lengths of the sides? : One side of a rectangular stage is 2 meters longer than the other. If the diagonal is 10 meters, then what are the lengths of the sides?
Answer by checkley77(3380) About Me  (Show Source):
You can put this solution on YOUR website!
The 2 sides and the diagonal form a right triangle. Thus we have the formula: a^2+b^2=c^2
x^2+(x+2)^2=10^2
x^2+x^2+4x+4=100
2x^2+4x+4-100=0
2x^2+4x-96=0
2(x^2+2x-48)=0
2(x+8)(x-6)=0
x-6=0
x=6 answer for the shorter side.
6+2=8 for the longer side.
Proof:
6^2+8^2=10^2
36=64=100
100=100

Question 161189: I am not certain if I need to use the a^ +b^ =c and then use a radical expression to reduce.
One side of a rectangular stage is
2 meters longer than the other. If the diagonal is 10 meters,
then what are the lengths of the sides?
Thank you,
Tracy
: I am not certain if I need to use the a^ +b^ =c and then use a radical expression to reduce.
One side of a rectangular stage is
2 meters longer than the other. If the diagonal is 10 meters,
then what are the lengths of the sides?
Thank you,
Tracy

Answer by ankor@dixie-net.com(4484) About Me  (Show Source):
You can put this solution on YOUR website!
One side of a rectangular stage is 2 meters longer than the other.
If the diagonal is 10 meters, then what are the lengths of the sides?
:
Actually it's:
a^2 + b^2 = c^2
:
In this problem call one side x:
Let x = a
then
(x+2) = b
and
c = 10
:
Substituting in our formula:
x^2 + (x+2)^2 = 10^2
:
FOIL (x+2)(x+2)
x^2 + (x^2 + 4x + 4) = 100
:
Combine like terms, arrange as a quadratic equation
x^2 + x^2 + 4x + 4 - 100 = 0
2x^2 + 4x - 96 = 0
:
Factor
(2x - 12)(x + 8) = 0
;
We want the positive solution here
2x = 12
x = 6 meters is the 1st side
then
6 + 2 = 8 meters is the 2nd side
:
:
We can check that: 6^2 + 8^2 = 10^2
:
Was this understandable? Any questions?

Question 160202: how do i use the Pythagorean theorem to show how the distance formula was derived.: how do i use the Pythagorean theorem to show how the distance formula was derived.
Answer by nerdybill(1039) About Me  (Show Source):
You can put this solution on YOUR website!
This web site explains it in detail:
http://www.purplemath.com/modules/distform.htm
.
If you still have trouble, write back.

Question 157689: A= 4B
B= ?
C= B-20
What is B equal to.
: A= 4B
B= ?
C= B-20
What is B equal to.

Answer by gonzo(428) About Me  (Show Source):
You can put this solution on YOUR website!
here goes .......................
A = 4B
C = B-20
solve for B
pythagorean formula is C^2 = A^2 + B^2
substituting to get all unknowns in terms of B, equation becomes
(B-20)^2 = (4B)^2 + B^2
multiplying out, formula becomes
B^2 - 40B + 400 = 4B^2 + B^2
combining like terms, formula becomes
-4B^2 - 40B + 400 = 0
multiplying left hand side of equation and right hand side of equation by -1 and formula becomes
4B^2 + 40B - 400 = 0
dividing both sides of the equation by 4 and the equation becomes
B^2 + 10B - 400 = 0
answer is not evident by inspection so use quadratic formula to get the roots.
quadratic formula is x = ((-b) + sqrt(b^2-4*a*c))/(2*a)
and x = ((-b) - sqrt(b^2+4*a*c))/(2*a)
where
-b = -10
b^2-4*a*c = (10^2 - 4*1*(-100) = 100 - (-400) = 500
2a = 2
solving we get B = 6.180339888 or B = -16.180339888.
since B can't be negative, the answer is B = 6.180339888.
substituting for B in the original equation derived from the pythagorean formula, we get
B^2 + 10*B - 100 = (6.180339888)^2 + 10*(6.180339888) - 100
= 38.19660113 + 61.80339888 - 100 = 0 which becomes
100 - 100 = 0
which becomes 0 = 0 proving formula is correct.
answer is B = 6.180339888 = 6.18 rounded to nearest hundredth.


Question 156438: The length of rectangle is 3 cm more than 3 times the width and 1 cm less than the length of a
diagonal. Find the length of the rectangle
: The length of rectangle is 3 cm more than 3 times the width and 1 cm less than the length of a
diagonal. Find the length of the rectangle

Answer by gonzo(428) About Me  (Show Source):
You can put this solution on YOUR website!
width = w
length = 3w + 3 (3 times the width plus 3 centimeters)
diagonal = 3w + 4 (length is 1 cm less than diagonal which means diagonal is 1 cm more then length (3w + 3 is the length + 1 = 3w + 4 is the diagonal)).
solve for w using pythagorean theorem (length squared plus width squared = diagonal squared)since the diagonal is the hypotenuse of a right triangle formed by the length and the width and the diagonal.
equation becomes:
length (3w+3) squared plus width (w) squared = hypotenuse (3w+4) squared.
becomes (3w+3)^2 + w^2 = (3w+4)^2.
becomes 9w^2 + 18w + 9 + w^2 = 9w^2 + 24w + 16
becomes w^2 - 6w - 7 = 0
becomes (w-7) * (w+1) = 0
w = 7 or w = -1.
can't be -1 so w = 7
w = 7 then length = 3w + 3 = 24 and diagonal = 3w + 4 = 25.
width = 7
length = 24
diagonal = 25
check pythagorean theorem 7^2 + 24^2 = 25^2
becomes 49 plus 576 = 625
becomes 625 = 625.







Question 155822: how will you factor 2x^2-178x-14280=0
(2x ) (x ) << I cant find the factors
: how will you factor 2x^2-178x-14280=0
(2x ) (x ) << I cant find the factors

Answer by stanbon(18723) About Me  (Show Source):
You can put this solution on YOUR website!
how will you factor 2x^2-178x-14280=0
(2x ) (x ) << I cant find the factors
-------------------------------------------
(x-140)(2x+102)
--------------------
How to do these?
Consider b^2-4ac = 178^2-4*2*-14280 = 145924
Take the sqrt to get 382
Add -b = 178 to get 560
Divide by 2a = 4 to get 140
So, one of the factors is (x-140)
Divide 14280 by 140 to get 102
----------
The other factor must be 2x+102
Check it out to see if it is correct.
========================================
Cheers,
Stan H.

Question 150635: the length of a leg of a right triangle is two times the length of the other, and the hypotenuse is 25.What is the length of the longer leg?
: the length of a leg of a right triangle is two times the length of the other, and the hypotenuse is 25.What is the length of the longer leg?

Answer by jim_thompson5910(9162) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=length of first leg and y=length of second leg


Since the "length of a leg of a right triangle is two times the length of the other", this means that y=2x. So in this case "y" is the longer leg.


So with the use of Pythagoreans theorem, we get

x^2+y^2=25^2


x^2+y^2=625 Square 25 to get 625


x^2+(2x)^2=625 Plug in y=2x


x^2+4x^2=625 Square 2x to get 4x^2


5x^2=625 Add


x^2=125 Divide both sides by 5.


x=sqrt(125) Take the square root of both sides. Note: only the positive square root is considered.


x=5*sqrt(5) Simplify the square root.



So the length of one leg is x=5*sqrt(5) (which approximates to x=11.18) and the length of the longer leg is y=2*5*sqrt(5)=10*sqrt(5) (which approximates to y=22.36)




Question 150498: Are there any other shapes that can be formed of the side of the side of the triangle besides squares that can complete the formula for example a hexagon? I have use a circle and that works if you use the length of the sides as the diameters. I think this is because of the square in the r2 is essentially the same as Pythagoras.: Are there any other shapes that can be formed of the side of the side of the triangle besides squares that can complete the formula for example a hexagon? I have use a circle and that works if you use the length of the sides as the diameters. I think this is because of the square in the r2 is essentially the same as Pythagoras.
Answer by Edwin McCravy(2033) About Me  (Show Source):
You can put this solution on YOUR website!
Are there any other shapes that can be formed of the side of the side of the triangle besides squares that can complete the formula for example a hexagon? I have use a circle and that works if you use the length of the sides as the diameters. I think this is because of the square in the r2 is essentially the same as Pythagoras.

All you need is that all three figures be similar
plane figures, that is, have the exact same shape.

Edwin

Question 148953: Greg is making a bike ramp in the shape of a right triangle. The base of the ramp is 4 inches more than twice its height, and the length of the incline is 4 inches less than three times its height. How high is the ramp? My question is in setting up the problem-do I have 2x+4 and 3x-4 for the formula c2=a2 + b2?: Greg is making a bike ramp in the shape of a right triangle. The base of the ramp is 4 inches more than twice its height, and the length of the incline is 4 inches less than three times its height. How high is the ramp? My question is in setting up the problem-do I have 2x+4 and 3x-4 for the formula c2=a2 + b2?
Answer by mangopeeler07(442) About Me  (Show Source):
You can put this solution on YOUR website!
x=height
2x+4=base
3x-4=incline

Therefore
x=a
2x+4=b
3x-4=c

These are the values to plug into a^2+b^2=c^2.

Question 148741: Hypotenuse of right angle is 60 cm. if the leg is five cm longer than the other leg, what is lenght of the legs.
I know the formula is c^2= a^2 + b^2
60^2= x^2 + (x+5)^2
60^2= x^2 + x^2 +10x +25
3600= 2x^2 + 10x + 25
Now what are we solving 4 x?
: Hypotenuse of right angle is 60 cm. if the leg is five cm longer than the other leg, what is lenght of the legs.
I know the formula is c^2= a^2 + b^2
60^2= x^2 + (x+5)^2
60^2= x^2 + x^2 +10x +25
3600= 2x^2 + 10x + 25
Now what are we solving 4 x?

Answer by oscargut(666) About Me  (Show Source):
You can put this solution on YOUR website!
3600= 2x^2 + 10x + 25
then
2x^2+10x+25-3600=0
2x^2+10x-3575=0
x = (-10 +- sqrt( 10^2-4*2*(-3575) ))/(2*2) =
x = (-10 +- sqrt( 28700 ))/(2*2) =
x = (-10 +- sqrt( 28700 ))/(4)
then solutions are x = (-10 + sqrt( 28700 ))/(4) and x = (-10 - sqrt( 28700 ))/(4)
positive solution is
x = (-10 + sqrt( 28700 ))/(4) =39.85 (aprox)
So legs are 39.85 and 44.85 aprox
Question 148741: Hypotenuse of right angle is 60 cm. if the leg is five cm longer than the other leg, what is lenght of the legs.
I know the formula is c^2= a^2 + b^2
60^2= x^2 + (x+5)^2
60^2= x^2 + x^2 +10x +25
3600= 2x^2 + 10x + 25
Now what are we solving 4 x?
: Hypotenuse of right angle is 60 cm. if the leg is five cm longer than the other leg, what is lenght of the legs.
I know the formula is c^2= a^2 + b^2
60^2= x^2 + (x+5)^2
60^2= x^2 + x^2 +10x +25
3600= 2x^2 + 10x + 25
Now what are we solving 4 x?

Answer by tennisbuff07(20) About Me  (Show Source):
You can put this solution on YOUR website!
yes, you just solve for x (which is one side) and figure out what x+5 is to find the other side. put those two values back in the formula to test your answer and make sure that the pythagorean theorum still works.

Question 148438: Let cos beta =a .Find the expression for cos 2beta and sin 2beta in terms of a
and hence confirm that - cos(square)2beta + sin(square)2beta = 1
: Let cos beta =a .Find the expression for cos 2beta and sin 2beta in terms of a
and hence confirm that - cos(square)2beta + sin(square)2beta = 1

Answer by stanbon(18723) About Me  (Show Source):
You can put this solution on YOUR website!
Let cos(beta) =a/1; this implies that x = a and r=1
Therefore y = sqrt(1-a^2)
Therefore sin(beta)= [sqrt(1-a^2)]/r
-------------------------------------
Find the expression for cos(2beta) and sin(2beta) in terms of a:
cos(2beta) = cos^2(beta)-sin^2(beta
= a^2 - [(1-a^2)/r^2]
------------------------------------ ------
sin(2beta) = 2*sin(beta)*cos(beta)
= 2 * sqrt(1-a^2)/r]
--------------------------
and hence confirm that - cos^2(2beta) + sin^2(2beta) = 1
------------------
Subsitute to confirm that statement is true.
====================
Cheers,
Stan H.

Question 147605: The hypotenuse of a right triangle is 2.5 units long. The longer leg is 1.8 units longer than the shorter leg. Find the lengths of the sides of the triangle.: The hypotenuse of a right triangle is 2.5 units long. The longer leg is 1.8 units longer than the shorter leg. Find the lengths of the sides of the triangle.
Answer by edjones(2391) About Me  (Show Source):
You can put this solution on YOUR website!
c=2.5
a=b+1.8
a^2+b^2=c^2
(b+1.8)^2+b^2=(2.5)^2
b^2+3.6b+3.24+b^2=6.25
2b^2+3.6b-3.01=0
b=.621512
a=2.42151
c=2.5
.
Ed
.
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax^2+bx+c=0 (in our case 2x^2+3.6x+-3.01 = 0) has the following solutons:

x[12] = (b+-sqrt( b^2-4ac ))/2\a

For these solutions to exist, the discriminant b^2-4ac should not be a negative number.

First, we need to compute the discriminant b^2-4ac: b^2-4ac=(3.6)^2-4*2*-3.01=37.04.

Discriminant d=37.04 is greater than zero. That means that there are two solutions:  x[12] = (-3.6+-sqrt( 37.04 ))/2\a.

x[1] = (-(3.6)+sqrt( 37.04 ))/2\2 = 0.621512405470294
x[2] = (-(3.6)-sqrt( 37.04 ))/2\2 = -2.42151240547029

Quadratic expression 2x^2+3.6x+-3.01 can be factored:
2x^2+3.6x+-3.01 = (x-0.621512405470294)*(x--2.42151240547029)
Again, the answer is: 0.621512405470294, -2.42151240547029. Here's your graph:
graph( 500, 500, -10, 10, -20, 20, 2*x^2+3.6*x+-3.01 )

Question 146958: Diagnal brace. The width of a retangular gate is 2 meters (m) larger than its heiht. The diagonal brace measures (Square root) 6 m. Find the width and height.: Diagnal brace. The width of a retangular gate is 2 meters (m) larger than its heiht. The diagonal brace measures (Square root) 6 m. Find the width and height.
Answer by edjones(2391) About Me  (Show Source):
You can put this solution on YOUR website!
We have a right triangle of height h, width h+2, and hypotenuse sqrt(6).
a^2+b^2=c^2
h^2+(h+2)^2=sqrt(6)^2
h^2+h^2+4h+4=6
2h^2+4h-2=0
2(h^2+2h-1)=0
h^2+2h =1
h^2+2h+1=1+1 completing the square.
(h+1)^2=2
h+1=+-sqrt(2) Square root of each side.
h= -1+sqrt(2) m
w= 1+sqrt(2) m
.
Ed

Question 147189: I need an explanation of why the Pythatgorean theorem can be used only for right triangles that an 8th grader can understand. What I know is that the Pythagorean Theorem is a special case of the Law of Cosines where the Cos(c) is equal to zero which only happens when c=90 degrees. But I don't think an 8th grader has had the law of cosines yet. I'd really appreciate some help with this. Thanks.: I need an explanation of why the Pythatgorean theorem can be used only for right triangles that an 8th grader can understand. What I know is that the Pythagorean Theorem is a special case of the Law of Cosines where the Cos(c) is equal to zero which only happens when c=90 degrees. But I don't think an 8th grader has had the law of cosines yet. I'd really appreciate some help with this. Thanks.
Answer by Edwin McCravy(2033) About Me  (Show Source):
You can put this solution on YOUR website!
Edwin's solution:
I need an explanation of why the Pythatgorean theorem can be used only for right triangles that an 8th grader can understand. What I know is that the Pythagorean Theorem is a special case of the Law of Cosines where the Cos(c) is equal to zero which only happens when c=90 degrees. But I don't think an 8th grader has had the law of cosines yet. I'd really appreciate some help with this. Thanks.

Suppose you had this triangle, which is not necessarily a right triangle:

drawing(400,240,-4,4,-1,3, triangle(-1.8,0,3.2,0,0,2.4),
locate(3.2,0,B), locate(-2,0,A), locate(0,2.7,C), locate(1.6,1.6,a),
locate(-1,1.6,b), locate(.7,0,c)

 )

You only know that a^2+b^2=c^2 but you don't know necessarily 
that angle C is 90°.

Now you construct another triangle, this time a RIGHT triangle DEF
with the SAME SIZE legs, a and b, but with its hypotenuse
f not given to be equal to c:

drawing(400,240,-4,4,-1,3, triangle(-1.8,0,3.2,0,0,2.4),
locate(3.2,0,E), locate(-2,0,D), locate(0,2.7,F), locate(1.6,1.6,a),
locate(-1,1.6,b), locate(-.2,2.1,'90°'),locate(.7,0,f) )

But we know that the Pythagorean theorem DOES hold true for triangle
DEF because we constructed it so that it is a right triangle with
angle E being a right angle. Therefore

a^2+b^2=f^2

And we are given that

a^2+b^2=c^2

So f^2=c^2 because both are equal to a^2+b^2.

and we can take positive square roots of both sides:

sqrt(f^2)=sqrt(c^2)

or f = c

Now we have all three sides of triangle DEF equaling 
all three corresponding sides of triangle ABC, so the
two triangles are congruent, and therefore angle A
equals angle E which equals 90°, for they are corresponding
parts of congruent triangles. Therefore ABC is a
right triangle.

Therefore all we need know is that a^2+b^2=c^2 to be
able to conclude that triangle ABC is a right triangle.

So the only time the Pythagorean theorem works is when we
have a right triangle.

Edwin
Question 147189: I need an explanation of why the Pythatgorean theorem can be used only for right triangles that an 8th grader can understand. What I know is that the Pythagorean Theorem is a special case of the Law of Cosines where the Cos(c) is equal to zero which only happens when c=90 degrees. But I don't think an 8th grader has had the law of cosines yet. I'd really appreciate some help with this. Thanks.: I need an explanation of why the Pythatgorean theorem can be used only for right triangles that an 8th grader can understand. What I know is that the Pythagorean Theorem is a special case of the Law of Cosines where the Cos(c) is equal to zero which only happens when c=90 degrees. But I don't think an 8th grader has had the law of cosines yet. I'd really appreciate some help with this. Thanks.
Answer by mangopeeler07(442) About Me  (Show Source):
You can put this solution on YOUR website!
Here is why the Pythagorean Theorem can only be used to solve right triangles. The Pythagorean Theorem is c^2=a^2+b^2 with a and b the length of the legs of the triangle and c as the hypotenuse, or the longest side. It has variations too, like c^2>a^2+b^2 and c^2<a^2+b^2. These three are used to figure out, with given any angles, whether a triangle is right, obtuse or acute (respectively) by plugging in the lengths given. If c^2>a^2+b^2 or c^2<a^2+b^2 holds true, than the triangle is obtuse or acute. But if c^2=a^2+b^2 holds true, than the triangle is right, and it has to be right. You are probably more familiar with this version: c^2=a^2+b^2. It is only true for right triangles, because of the unique relationship among the three side lengths, which never holds true for any other type of triangle. That is why this variation of it (with the = sign) can only be used for right triangles and right triangles only. Right triangles are the only triangles that make this c^2=a^2+b^2 true.

Question 146085: how, in simple terms, can we prove the Pythagorean Theorem?: how, in simple terms, can we prove the Pythagorean Theorem?
Answer by nerdybill(1039) About Me  (Show Source):
You can put this solution on YOUR website!
The web already has many proofs of Pythagorean theorem.
I would suggest you go to:
www.google.com
and enter "proof pythagorean"
you will find many examples along with explanations.
.
Here is one example:
http://mathforum.org/isaac/problems/pythagthm.html

Question 145818: An overhead wire stretches from the service drop that is 20ft from the ground,on a building to an insulator on a pole 35 ft from the ground. How long is the wire if the pole and building are 48 ft apart?(Assume ground is level.)Round answer to tenths.: An overhead wire stretches from the service drop that is 20ft from the ground,on a building to an insulator on a pole 35 ft from the ground. How long is the wire if the pole and building are 48 ft apart?(Assume ground is level.)Round answer to tenths.
Answer by nerdybill(1039) About Me  (Show Source):
You can put this solution on YOUR website!
An overhead wire stretches from the service drop that is 20ft from the ground,on a building to an insulator on a pole 35 ft from the ground. How long is the wire if the pole and building are 48 ft apart?(Assume ground is level.)Round answer to tenths.
.
The first thing you need to do is to draw a diagram!
.
From your diagram, you'll notice that the ground, building and pole forms a "right triangle". Because it is a right triangle (one of the interior angle of the triangle is 90 deg), we can apply Pythagorean theorem.
.
Let x = length of the overhead wire
then
x^2 = 48^2 + (35-20)^2
x^2 = 48^2 + 15^2
x^2 = 2304 + 225
x^2 = 2529
x = 50.3 ft


Question 145829: Solve for the unknown side in the following right triangle. (side AC is the hypotenuse.) Round your answer to two places, where applicable.Side AB ? Side BC12 Side AC 19: Solve for the unknown side in the following right triangle. (side AC is the hypotenuse.) Round your answer to two places, where applicable.Side AB ? Side BC12 Side AC 19
Answer by nerdybill(1039) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for the unknown side in the following right triangle. (side AC is the hypotenuse.) Round your answer to two places, where applicable.Side AB ? Side BC12 Side AC 19
From Pythagorean theorem we know:
(AC)^2 = (AB)^2 + (BC)^2
plugging in what was given:
(19)^2 = (AB)^2 + (12)^2
(19)^2 = (AB)^2 + (12)^2
361 = (AB)^2 + 144
361 - 144 = (AB)^2
217 = (AB)^2
14.73 = (AB)

Question 145831: You are to run a conduit diagonally across a parking lot that is 200 ft long and 60 ft wide.How much conduit will you need to complete this run? Round your answer to tenths.: You are to run a conduit diagonally across a parking lot that is 200 ft long and 60 ft wide.How much conduit will you need to complete this run? Round your answer to tenths.
Answer by nerdybill(1039) About Me  (Show Source):
You can put this solution on YOUR website!
Apply Pythagorean theorem
.
Let x = length of conduit
then
x^2 = 200^2 + 60^2
x^2 = 40000 + 3600
x^2 = 43600
x = 208.8 feet

Question 145431: The sum of the lengths of the diagonals of a rhombus of side 61 cm is 142 cm. What is (a) the difference in the lengths of the diagonals, (b) the area of the rhombus?
i can't get the solution out of it as i think i do not have enough informantion so i do not know how to solve it.
: The sum of the lengths of the diagonals of a rhombus of side 61 cm is 142 cm. What is (a) the difference in the lengths of the diagonals, (b) the area of the rhombus?
i can't get the solution out of it as i think i do not have enough informantion so i do not know how to solve it.

Answer by Edwin McCravy(2033) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of the lengths of the diagonals of a rhombus of side 61 cm is 142 cm. What is (a) the difference in the lengths of the diagonals, (b) the area of the rhombus?
i can't get the solution out of it as i think i do not have enough informantion so i do not know how to solve it.

Yes, there's enough information. First we draw a rhombus with 61cm sides:
drawing(400,100,-65,65,-12,12,  
<BR>

line(-60,0,0,-11),<BR>
line(0,-11,60,0),<BR>
line(60,0,0,11),<BR>
line(-60,0,0,11),<BR>
locate(30,11,61),<BR>
locate(-30,11,61),<BR>
locate(30,-6,61),<BR>
locate(-30,-6,61)<BR>
 )
Now draw in the longer diagonal and label its length x cm.
drawing(400,100,-65,65,-12,12,  
<BR>

line(-60,0,0,-11),<BR>
line(0,-11,60,0),<BR>
line(60,0,0,11),<BR>
line(-60,0,0,11),<BR>
locate(30,11,61),<BR>
locate(-30,11,61),<BR>
locate(30,-6,61),<BR>
locate(-30,-6,61)<BR>
line(-60,0,60,0), locate(0,5,x)<BR>
 )
Now take away the bottom half of the rhombus,
and you have an isosceles triangle. Label the
angle alpha:
drawing(400,100,-65,65,-12,12,  
<BR>

triangle(-60,0,60,0,0,11),<BR>
locate(30,11,61), locate(0,5,x),<BR>
locate(-30,11,61),<BR>
locate(0,10,alpha),<BR>
line(-60,0,60,0)
<BR>

 )
We use the law of cosines:
x^2=61^2+61^2-2(61)(61)cos(alpha)
x ^2=7442-7442cos(alpha)
That's one equation we will use.
Now let's go back to the original rhombus.
drawing(400,100,-65,65,-12,12,  
<BR>

line(-60,0,0,-11),<BR>
line(0,-11,60,0),<BR>
line(60,0,0,11),<BR>
line(-60,0,0,11),<BR>
locate(30,11,61),<BR>
locate(-30,11,61),<BR>
locate(30,-6,61),<BR>
locate(-30,-6,61),<BR>
locate(0,10,alpha),<BR>
locate(-50,2.4,'180°-'),<BR>
locate(-35,2.4,alpha)<BR>
 )
Since two angles of a parallelogram
which are next to each other are
supplementary, we label the angle
180°-alpha

Now we draw the other diagonal and label its length y cm:
drawing(400,100,-65,65,-12,12,  
<BR>

line(-60,0,0,-11),<BR>
line(0,-11,60,0),<BR>
line(60,0,0,11),<BR>
line(-60,0,0,11),<BR>
locate(30,11,61),<BR>
locate(-30,11,61),<BR>
locate(30,-6,61),<BR>
locate(-30,-6,61),<BR>
locate(0,10,alpha),<BR>
locate(-50,2.4,'180°-'),<BR>
locate(-35,2.4,alpha),<BR>
line(0,11,0,-11),<BR>
locate(-4,2.4,y)
<BR>

 )
Take away the right half and we have
another isosceles triangle.
drawing(400,100,-65,65,-12,12,  
<BR>

line(-60,0,0,-11),<BR>
line(-60,0,0,11),<BR>
locate(30,11,61),<BR>
locate(-30,11,61),<BR>
locate(30,-6,61),<BR>
locate(-30,-6,61),<BR>
locate(-50,2.4,'180°-'),<BR>
line(0,11,0,-11),<BR>
locate(-4,2.4,y)
<BR>

 )
We use the law of cosines again:
y^2=61^2+61^2-2(61)(61)cos(90-alpha)
y ^2=7442-7442cos(90-alpha)
Now we use the fact that cos(90-alpha)=-cos(alpha)
y ^2=7442-7442(-cos(alpha))
or
y^2=7442+7442cos(alpha)
Take that equation with the other one:
x^2=7442-7442cos(alpha)
y^2=7442+7442cos(alpha)
Now we add equals to equals. Adding
the left sides gives x^2+y^2 and
adding the right sides, the cosine terms
cancel out. So we have:
x^2+y^2=14884
Now we are told that the sum of the diagonals
is 142 cm., so we have the equation
x+y=142
So we have this system of equations:
x^2+y^2=14884
x+y=142
Can you solve that by solving the second for
one of the letters and substituting into the
first equation? If not post again asking
how.
Solution to that system of equations: x=120cm, y=22cm
Those are the lengths of the diagonals.
The difference is just 120cm-22cm=98cm.
Now since the diagonals of a rhombus are
perpendicular bisectors of each other, the
shorter diagonal, which is 22 cm is bisected
by the long diagonal, and so each half is
11 cm.
drawing(400,100,-65,65,-12,12,  <BR>
line(0,-11,0,11),<BR>
line(-60,0,0,-11),<BR>
line(0,-11,60,0),<BR>
line(60,0,0,11),<BR>
line(-60,0,0,11),<BR>
locate(30,11,61),<BR>
locate(-30,11,61),<BR>
locate(30,-6,61),<BR>
locate(-30,-6,61)<BR>
line(-60,0,60,0), locate(0,7,11), locate(0,-5,11)<BR>
 )
To find the area, take away the bottom half, and
we have this triangle to find the area of:
drawing(400,100,-65,65,-12,12,  
<BR>

line(60,0,0,11),<BR>
line(-60,0,0,11),<BR>
locate(30,11,61),<BR>
locate(-30,11,61),<BR>
line(0,0,0,11),<BR>
line(-60,0,60,0), locate(0,7,11)<BR>
 )
The base of that triangle is 120cm, and its
height is 11cm
A = (1/2)bh=(1/2)(120cm)(11cm)=660cm^2
So we double that to find the total area of the rhombus.
Answer = 1320cm^2
Edwin

Question 145408: Find the length of the third side of the right triangle. Give an exact answer and an approximation to three decimal places. I could not find a triangle to input into my question and I could not copy and paste from another program. The bottom is about on inch long with an 8 below the left side is straight up and down about 1/2 inch with a 6 beside with a small box in the corner. the right is the length of the bottom only coming down to meet the bottom with the letter c on top. : Find the length of the third side of the right triangle. Give an exact answer and an approximation to three decimal places. I could not find a triangle to input into my question and I could not copy and paste from another program. The bottom is about on inch long with an 8 below the left side is straight up and down about 1/2 inch with a 6 beside with a small box in the corner. the right is the length of the bottom only coming down to meet the bottom with the letter c on top.
Answer by 24HoursTutor.com(40) About Me  (Show Source):
You can put this solution on YOUR website!
If your triangle looks like what I have imagined it to be from your description then this is the solution :
According to the Pythagoras theorem : a^2+ b^2 = c^2
Here a = 8, b = 6
Which means 8^2 + 6^2 = c^2
64 + 36 = c^2
100 = c^2
c = sqrt(100) = 10
Hence, the third side of the triangle is 10
The above question is solved by one of the experts from 24HoursTutor.com
We provide live 1:1 online homework help
1. 24X7 tutors available
2. Certified tutors
3. Only for $9.99/hr








Question 145065: If the length of a side of a square ABCD is 5, find the length of AC
: If the length of a side of a square ABCD is 5, find the length of AC

Answer by seema230480(3) About Me  (Show Source):
You can put this solution on YOUR website!
AC is the hypotenuse of the right triangle ACD
Formula for hypotenuse = ^((Length)*(length)+(breadth)*(breadth))
=^(5*5+5*5)
=^50
=7.07 units

Question 145064: What is the length of a side of a square whose diagonal measures 4.24 ft?: What is the length of a side of a square whose diagonal measures 4.24 ft?
Answer by nerdybill(1039) About Me  (Show Source):
You can put this solution on YOUR website!

Draw a diagram!
From it, you'll see that the diagonal and two sides form a right triangle.
Let x = length of a side of the square
then
x^2 + x^2 = 4.24^2
2x^2 = 4.24^2
2x^2 = 17.9776
x^2 = 8.9888
x = 3 feet

Question 145067: Find the length of a side of an equilateral triangle whose altitude is 17.32 cm.: Find the length of a side of an equilateral triangle whose altitude is 17.32 cm.
Answer by nerdybill(1039) About Me  (Show Source):
You can put this solution on YOUR website!
The key is that an "equilateral triangle" implies that ALL three sides are of equal lengths. Once you know that (if you draw a diagram), you can see that the "altitude" will bisect (divide it in half) one side of the triangle (at exactly 90 degrees). Now you can apply Pythagorean's theorem:
Let x = length of a side of the equilateral triangle
17.32^2 + (x/2)^2 = x^2
Solving for 'x' above will yield your answer.

Question 145066: Find the length of the altitude of an equilateral triangle whose side measures 6 feet.: Find the length of the altitude of an equilateral triangle whose side measures 6 feet.
Answer by nerdybill(1039) About Me  (Show Source):
You can put this solution on YOUR website!
When you see the term "equilateral triangle" it should immediately register that all three sides are equal!
And, that the altitude (h) bisects one side in half.
Since x = 6 feet (given in problem)
Draw the diagram above...
Now, you can apply Pythagorean's theorem:
h^2 + 3^2 = 6^2
h^2 + 9 = 36
h^2 = 27
h = sqrt(27)
h = sqrt(3*3*3)
h = 3sqrt(3)

Question 144665: Triangles HIJ and MNO are similar. The length of the sides of HIJ are 111, 96, and 108 centimeters. The length of the smallest side of MNO is 288 centimeters, what is the length of the longest side on MNO?
manual responses are 315 cm , 324 cm, 333cm 945cm. I don't even know where to start with only one side of MNO given.
: Triangles HIJ and MNO are similar. The length of the sides of HIJ are 111, 96, and 108 centimeters. The length of the smallest side of MNO is 288 centimeters, what is the length of the longest side on MNO?
manual responses are 315 cm , 324 cm, 333cm 945cm. I don't even know where to start with only one side of MNO given.

Answer by scott8148(2719) About Me  (Show Source):
You can put this solution on YOUR website!
the triangles are similar, which means that the ratio between corresponding sides is constant

smallest is to smallest as longest is to longest __ let x="longest side"

288/96=x/111 __ 3=x/111 __ 333=x

Question 143529: I just want to make sure I have the right answer, if I don't could you please explain the steps to me.
Problem---You are given a right triangle with the following lengths. Leg 1 = 2, Leg 2 = x, Hypotenuse = 8. Use the Pythagorean Theorem to find x. Make sure you include an equation.
Here is my answer
c^2 - a^2 = b^2
8^2 - 2^2 =
sqrt64 - sqrt4 =
sqrt60 =
Sqrt4 X 15 =
2 sqrt15 = X
Answer is 2 sqrt15 = x
: I just want to make sure I have the right answer, if I don't could you please explain the steps to me.
Problem---You are given a right triangle with the following lengths. Leg 1 = 2, Leg 2 = x, Hypotenuse = 8. Use the Pythagorean Theorem to find x. Make sure you include an equation.
Here is my answer
c^2 - a^2 = b^2
8^2 - 2^2 =
sqrt64 - sqrt4 =
sqrt60 =
Sqrt4 X 15 =
2 sqrt15 = X
Answer is 2 sqrt15 = x

Answer by jim_thompson5910(9162) About Me  (Show Source):
You can put this solution on YOUR website!
We basically have this triangle set up:

drawing(500,500,-0.5,2,-0.5,3.2,
<BR>

line(0,0,0,3),<BR>
line(0,3,2,0),<BR>
line(2,0,0,0),<BR>
locate(-0.2,1.5,2),<BR>
locate(1,-0.2,x),<BR>
locate(1,2,8)<BR>
)
Since we can see that the triangle has legs of 2 and x with a hypotenuse of 8, we can use Pythagoreans theorem to find the unknown side.


Pythagoreans theorem:

a^2+b^2=c^2 where a and b are the legs of the triangle and c is the hypotenuse



2^2+x^2=8^2 Plug in a=2, b=x, and c=8. Now lets solve for x


4 +  x  ^ 2 = 6 4 Square each individual term



 x  ^ 2 = 6 4 - 4 Subtract 4 from both sides


 x  ^ 2 = 6 0 Combine like terms


s q r t (  x  ^ 2 ) = s q r t ( 6 0 ) Take the square root of both sides


x=2*sqrt(15) Simplify the square root



So you are correct

Question 143241: find the measure of b if a = 10 and c = 16
I have figured it out as far as I can, but I am now stuck and I don't know what to do, so if you could put down every single step I would appreciate it!!!
: find the measure of b if a = 10 and c = 16
I have figured it out as far as I can, but I am now stuck and I don't know what to do, so if you could put down every single step I would appreciate it!!!

Answer by jim_thompson5910(9162) About Me  (Show Source):
You can put this solution on YOUR website!
We basically have a triangle like this set up:

drawing(500,500,-0.5,2,-0.5,3.2,
<BR>

line(0,0,0,3),<BR>
line(0,3,2,0),<BR>
line(2,0,0,0),<BR>
locate(-0.2,1.5,10),<BR>
locate(1,-0.2,x),<BR>
locate(1,2,16)<BR>
)
Since we can see that the triangle has legs of 10 and x with a hypotenuse of 16, we can use Pythagoreans theorem to find the unknown side.


Pythagoreans theorem:

a^2+b^2=c^2 where a and b are the legs of the triangle and c is the hypotenuse



10^2+x^2=16^2 Plug in a=10, b=x, and c=16. Now lets solve for x


1 0 0 +  x  ^ 2 = 2 5 6 Square each individual term



 x  ^ 2 = 2 5 6 - 1 0 0 Subtract 100 from both sides


 x  ^ 2 = 1 5 6 Combine like terms


s q r t (  x  ^ 2 ) = s q r t ( 1 5 6 ) Take the square root of both sides


x=2*sqrt(39) Simplify the square root



So our answer is x=2*sqrt(39) which is approximately x=12.49


So the value of b is b=2*sqrt(39) which is approximately b=12.49

Question 142488: If (x,12,13) is a Pythagoreantriple, then x = : If (x,12,13) is a Pythagoreantriple, then x =
Answer by benni1013(141) About Me  (Show Source):
You can put this solution on YOUR website!
The answer is 5. A pythagorean triple a^2+b^2=c^2 checks out very nicely.
Question 142488: If (x,12,13) is a Pythagoreantriple, then x = : If (x,12,13) is a Pythagoreantriple, then x =
Answer by stanbon(18723) About Me  (Show Source):
You can put this solution on YOUR website!
If (x,12,13) is a Pythagorean triple, then x =
------------
13^2 = 12^2 + x^2
x^2 = 13^2 - 12^2
x^2 = 169 - 144
x^2 = 25
x = 5
==========
Cheers,
Stan H.

Question 140716: My problem is C squared equals 8x squared(substituted for A) plus 15x squared(once again substituted)
Since the question is an odd one, i got my answer of 23x squared but the book got something different...
The book got 17x
i do not understand how they got that.
: My problem is C squared equals 8x squared(substituted for A) plus 15x squared(once again substituted)
Since the question is an odd one, i got my answer of 23x squared but the book got something different...
The book got 17x
i do not understand how they got that.

Answer by oscargut(666) About Me  (Show Source):
You can put this solution on YOUR website!
C^2=(8x)^2+(15x)^2
then
C^2= 64x^2+225x^2
C^2=289x^2
then
C= sqrt(289)x=17x

Question 139921: My problem is, A= Square root 75. B = Square root 6. How do I put in square roots in the site's calculator, nd if not, what's the answer to the problem?: My problem is, A= Square root 75. B = Square root 6. How do I put in square roots in the site's calculator, nd if not, what's the answer to the problem?
Answer by checkley77(3380) About Me  (Show Source):
You can put this solution on YOUR website!
A) sqrt75=5sqrt3=5*1.732=8.66 answer
B) sqrt6=2.45 answer.

Question 139343: Ok, I have a right triangle with an altitude of 8, the shorter side of the hypotenuse divided by the altitude is 4 and the longer side is represented by a. The shortest side of the triangle is 8.9 and the last side is represented by b. I need help finding a and b.: Ok, I have a right triangle with an altitude of 8, the shorter side of the hypotenuse divided by the altitude is 4 and the longer side is represented by a. The shortest side of the triangle is 8.9 and the last side is represented by b. I need help finding a and b.
Answer by scott8148(2719) About Me  (Show Source):
You can put this solution on YOUR website!
the altitude divides the large triangle into two smaller triangles, both of which are SIMILAR the the large triangle (and each other)

using ratios of similarity __ 4:8::8.9:b and 4:8::8:a

b=17.8 and a=16


trying to check the results using Pythagoras shows that the initial values have been rounded
__ a 4-8-8.9 triangle is NOT a right triangle
__ the 8.9 is actually 4sqrt(5)