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Percentage-and-ratio-word-problems/731171: In an art class, there are twice as many women as men.
What fraction of the class are women?

1 solutions

Answer 447016 by MathLover1(6622) About Me  on 2013-03-27 14:09:54 (Show Source):
You can put this solution on YOUR website!

Let number of women+=+x
if there are twice as many women as men, number of men+=+%281+%2F2%29+x
Total+=+%283+%2F+2%29+x
Fraction that are


Travel_Word_Problems/731160: hello i have a math question
1 solutions

Answer 447011 by MathLover1(6622) About Me  on 2013-03-27 13:57:54 (Show Source):
You can put this solution on YOUR website!
post your question here and you will get an answer


Matrices-and-determiminant/731134: How do I find the reduced row echelon?
X + y+ z=3
2x - y + z=2
4x – 2y +3z=5

1 solutions

Answer 447002 by MathLover1(6622) About Me  on 2013-03-27 12:17:29 (Show Source):
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your matrix is:


Row operation
1:

....add -2 times the 1st row to the 2nd row =>
Row operation
2:
.........add -4 times the 1st row to the 3rd row...=>

Row operation
3:
..............multiply the 2nd row by -1%2F3...=>...
Row operation
4:
....add 6 times the 2nd row to the 3rd row..=>...
Row operation
5:
...........add -1%2F3 times the 3rd row to the 2nd row...=>...
Row operation
6:
.....add -1 times the 3rd row to the 1st row...>...

Row operation
7:
....add -1 times the 2nd row to the 1st row...=>...


Money_Word_Problems/731116: t shirts cost 3 for 25 how much would i spend if i baught 7 tee shirts
1 solutions

Answer 447001 by MathLover1(6622) About Me  on 2013-03-27 11:53:35 (Show Source):
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if 3 t shirts cost 25 then 1 t shirt cost 25%2F3=8.3333333333333333333333333333333=8.33
and you would spend 7%2A8.33=+58.33 if you bought 7


Finance/731111: Which of the following is true of the roots of the equations x^2-6x+8=0?/p> A. They are opposite in sign and equal. B. They are opposite in sign and the larger
1 solutions

Answer 446996 by MathLover1(6622) About Me  on 2013-03-27 11:24:47 (Show Source):
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x%5E2-6x%2B8=0...first factor completely (or use quadratic formula) to find roots
x%5E2-6x%2B8=0.....write -6x as -4x-2x
x%5E2-4x-2x%2B8=0........group
%28x%5E2-4x%29-%282x-8%29=0
x%28x-4%29-2%28x-4%29=0
%28x-2%29%28x-4%29=0
roots:
if %28x-2%29=0...=>..x=2
if %28x-4%29=0...=>..x=4

so, your answer is: They are both positive.


test/730942: Let P(-3,6) and Q(10,1) be two points in the coordinate plane
Find an equation of the circle that contains P and Q and whose center is the midpoint of the segment PQ
1 solutions

Answer 446942 by MathLover1(6622) About Me  on 2013-03-26 21:41:29 (Show Source):
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The standard equation of a circle with center C(h,k) and radius r is as follows:
%28x-h%29%5E2+%2B+%28y+-k%29%5E2+=+r%5E2
so, we need to find h,+k, and r
since the circle that contains P and Q , the distance between them is equal to diameter of the circle:
Solved by pluggable solver: Distance Formula


The first point is (x1,y1). The second point is (x2,y2)


Since the first point is (-3, 6), we can say (x1, y1) = (-3, 6)
So x%5B1%5D+=+-3, y%5B1%5D+=+6


Since the second point is (10, 1), we can also say (x2, y2) = (10, 1)
So x%5B2%5D+=+10, y%5B2%5D+=+1


Put this all together to get: x%5B1%5D+=+-3, y%5B1%5D+=+6, x%5B2%5D+=+10, and y%5B2%5D+=+1

--------------------------------------------------------------------------------------------


Now use the distance formula to find the distance between the two points (-3, 6) and (10, 1)



d+=+sqrt%28%28x%5B1%5D-x%5B2%5D%29%5E2+%2B+%28y%5B1%5D+-+y%5B2%5D%29%5E2%29


d+=+sqrt%28%28-3+-+10%29%5E2+%2B+%286+-+1%29%5E2%29 Plug in x%5B1%5D+=+-3, y%5B1%5D+=+6, x%5B2%5D+=+10, and y%5B2%5D+=+1


d+=+sqrt%28%28-13%29%5E2+%2B+%285%29%5E2%29


d+=+sqrt%28169+%2B+25%29


d+=+sqrt%28194%29


d+=+13.9283882771841

==========================================================

Answer:


The distance between the two points (-3, 6) and (10, 1) is exactly sqrt%28194%29 units


The approximate distance between the two points is about 13.9283882771841 units



So again,


Exact Distance: sqrt%28194%29 units


Approximate Distance: 13.9283882771841 units




so, diameter d=13.9...=>...r=13.9%2F2...=>...r=6.95
now find midpoint:
Solved by pluggable solver: Midpoint


The first point is (x1,y1). The second point is (x2,y2)


Since the first point is (-3, 6), we can say (x1, y1) = (-3, 6)
So x%5B1%5D+=+-3, y%5B1%5D+=+6


Since the second point is (10, 1), we can also say (x2, y2) = (10, 1)
So x%5B2%5D+=+10, y%5B2%5D+=+1


Put this all together to get: x%5B1%5D+=+-3, y%5B1%5D+=+6, x%5B2%5D+=+10, and y%5B2%5D+=+1

----------------------------------------------------------------------------------------




Finding the x coordinate of the midpoint: Add up the corresponding x coordinates x1 and x2 and divide that sum by 2


X Coordinate of Midpoint = %28x%5B1%5D%2Bx%5B2%5D%29%2F2


X Coordinate of Midpoint = %28-3%2B10%29%2F2


X Coordinate of Midpoint = 7%2F2


X Coordinate of Midpoint = 3.5



So the x coordinate of the midpoint is 3.5


----------------------------------------------------------------------------------------


Finding the y coordinate of the midpoint: Add up the corresponding y coordinates y1 and y2 and divide that sum by 2


Y Coordinate of Midpoint = %28y%5B1%5D%2By%5B2%5D%29%2F2


Y Coordinate of Midpoint = %286%2B1%29%2F2


Y Coordinate of Midpoint = 7%2F2


Y Coordinate of Midpoint = 3.5


So the y coordinate of the midpoint is 3.5



===============================================================================


Summary:


The midpoint of the segment joining the two points (-3, 6) and (10, 1) is (3.5, 3.5).


So the answer is (3.5, 3.5)




center is (3.5, 3.5)=(h,+k)...so h=3.5 and k=3.5
%28x-h%29%5E2+%2B+%28y+-k%29%5E2+=+r%5E2...plug in h=3.5,k=3.5, and r=6.95
your equation is:

%28x-3.5%29%5E2+%2B+%28y+-3.5%29%5E2+=+6.95%5E2



Circles/730930: What is the centre and radius of the circle with the equation
2x^2+2y-12x+4y-15=0
1 solutions

Answer 446939 by MathLover1(6622) About Me  on 2013-03-26 21:17:31 (Show Source):
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2x%5E2%2B2y-12x%2B4y-15=0......here you missing y%5E2 to have a circle
I guess 2y should be 2y%5E2, but it also might be 4y%5E2
let's do it with 2y%5E2
2x%5E2%2B2y%5E2-12x%2B4y-15=0....write it in the standard form
The standard equation of a circle with center C(h,k) and radius r is as follows:
%28x-h%29%5E2+%2B+%28y-k%29%5E2+=+r%5E2
2x%5E2%2B2y%5E2-12x%2B4y-15=0..put all terms with x and x%5E2 together and all terms with y and y%5E2+ together using brackets
%282x%5E2-12x%29%2B%282y%5E2%2B4y%29-15=0......complete the square within each bracket
%282x%5E2-12x%2B18%29-18%2B%282y%5E2%2B4y%2B2%29-2-15=0
2%28x%5E2-6x%2B9%29%2B2%28y%2B2x%2B1%29-35=0
2%28x-3%29%5E2%2B2%28y%2B1%29%5E2-35=0
2%28x-3%29%5E2%2B2%28y%2B1%29%5E2=35 ....both sides divide by 2

2%28x-3%29%5E2%2F2%2B2%28y%2B1%29%5E2%2F2=35%2F2
%28x-3%29%5E2%2B%28y%2B1%29%5E2=17.5

so,the center and radius of the circle are:
C(3,-1)
r=4.18



Exponential-and-logarithmic-functions/730922: What is the exponential function (y=ab^x) whose graph passes through the points of (-1, 48) and (2, 6).
1 solutions

Answer 446920 by MathLover1(6622) About Me  on 2013-03-26 19:55:12 (Show Source):
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given:
y=ab%5Ex whose graph passes through the points of
(-1,+48) and (2, 6)
Make a system of equations with the points by substituting them for x and y:
48+=+ab%5E%28-1%29.........1
6+=+ab%5E2.................2
48+=+a%281%2Fb%29.........1
6+=+ab%5E2.................2
take
48+=+a%281%2Fb%29.........1 and solve for a
48b=+a..........substitute in 2
6+=+%2848b%29b%5E2.................2 solve for b
6+=+48b%5E3
6%2F48+=+b%5E3
1%2F8+=+b%5E3
root%283%2C1%2F8%29+=+b
root%283%2C1%29%2Froot%283%2C2%5E3%29+=+b
b=1%2F2
now find a
a+=+48%281%2F2%29
a+=+48%2F2
a=24
The exponential function is y+=+24%281%2F2%29%5Ex.




Triangles/730645: The sides of a triangle measure 16, 30, and 34. Which type of triangle is it?
1 solutions

Answer 446775 by MathLover1(6622) About Me  on 2013-03-26 09:07:01 (Show Source):
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Types of Triangles:
Isosceles: The Isosceles triangle shown on the left has two equal sides and two equal angles.
Equilateral: The Equilateral triangle shown on the left has three equal sides and three equal angles. Each angle is 60°
Scalene: The Scalene Triangle has no congruent sides. In other words, each side must have a different length.
Obtuse: The Obtuse Triangle has an obtuse angle (an obtuse angle has more than 90°).
Acute: The Acute Triangle has three acute angles (an acute angle measures less than 90°)
Right+Triangles: A right triangle has one 90°.
you are given: the sides of a triangle measure 16, 30, and 34
as you can see, all sides are different in length; so, your triangle is NOT an Isosceles nor Equilateral triangle
it could be Scalene (because has no congruent sides), could be Obtuse (might have an obtuse angle),could be Acute (might have an Acute angle), or could be Right Triangle (might have an right angle angle).
let's check first is it Right Triangle because we can do it using Pythagorean theorem:
let's sides 16 and 30 be legs, and 34 hypotenuse
then we have 34%5E2=16%5E2%2B30%5E2 if this true, we have a Right Triangle
1156=256%2B900
1156=1156...so, this is true and your triangle IS Right Triangle
but, it is also a scalene triangle with a right angle


test/730637: 9m=7m+16
1 solutions

Answer 446766 by MathLover1(6622) About Me  on 2013-03-26 08:38:13 (Show Source):


logarithm/730525: x=log(100)^10
1 solutions

Answer 446712 by MathLover1(6622) About Me  on 2013-03-25 21:06:31 (Show Source):


logarithm/730495: how to solve log[5](90)using change of base formula
1 solutions

Answer 446692 by MathLover1(6622) About Me  on 2013-03-25 19:55:49 (Show Source):
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log%285%2C90%29=%28log%2890%29%29%2F%28log%285%29%29....in base 10
=log%283%5E2%2A2%2A5%29%2Flog%285%29
=%28log%283%5E2%29%2Blog%282%29%2Blog%285%29%29%2Flog%285%29
=%282log%283%29%2Blog%282%29%2Blog%285%29%29%2Flog%285%29
=2.7958889470453636409392392873060701381191307318260948
=2.8


Quadratic_Equations/730485: I need help in writing a word problem involving a quadratic function. And I need to explain it in terms someone not in class could understand it, please. I am in the home stretch of my class and would really appreciate the help. Thank you
1 solutions

Answer 446691 by MathLover1(6622) About Me  on 2013-03-25 19:47:19 (Show Source):
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A function f is a quadratic function if f%28x%29+=+ax%5E2+%2B+bx+%2B+c where a, b, and c are real numbers and not equal to 0.
The graph of a quadratic function is a parabola. The most basic aid in graphing a parabola is knowing whether a+%3E+0 (the graph opens upward) or a+%3C+0 (the graph opens downward).
The two simplest quadratic functions are f%28x%29+=+x%5E2 and g%28x%29+=+-+x%5E2 .
a word problem involving a quadratic function:
An inquiry shows that 60000 students will attend a theater play in one week if the ticket price is 40 dollars. Suppose that for every 2.50 dollars added to the ticket price, 2000 fewer students will attend the play.
1. What ticket price will give the greatest revenue for the week?
2. what is the approximate maximum possible profit for the week if the theater play spends approximately 1.5 million dollars to have the play showed for one week?
answer:
1. Let x be the number of times $2.50 is added to the ticket price (and 2000 fewer students attend).
Revenue for the week is %2840%2B2.50x%29%2860000-2000x%29
= 2.5%2816%2Bx%29%2A2000%2830-x%29
= 5000%2816%2Bx%29%2830-x%29
= 5000%28-x%5E2%2B14x%2B480%29
Thus the greatest revenue is given by the maximum of function -x%5E2%2B14x%2B480. It is a quadratic function with a maximum of -b%2F2a=+-14%2F%28-2%29=7 where 7 is the value of x for which the revenue will be greatest.
To answer the question, calculate the corresponding ticket price by adding $2.50%2A7 to the original $40=40%2B2.5%2A7=57.50.
2. Profit=revenue+-+spending
Since spendings are fixed, maximum profit is obtained when maximum revenue is obtained as above, for x=7.
Max+_profit=5000%28-7%5E2%2B14%2A7%2B480%29-1500000
=$1145000



test/730477: How do you work a problem like-
x-2(x-6)=2-(4x+5)
1 solutions

Answer 446685 by MathLover1(6622) About Me  on 2013-03-25 19:24:53 (Show Source):
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x-2%28x-6%29=2-%284x%2B5%29......first multiply 2%28x-6%29
x-%282x-12%29=2-%284x%2B5%29....eliminate parentheses, both have negative sign in front of them, so you will change signs inside of them
x-2x%2B12=2-4x-5
-x%2B12=-4x-3
-x%2B4x=-12-3
3x=-15
x=-15%2F3
x=-5


Travel_Word_Problems/730470: How is 3 and a half hours at 45 mph equal to 157.5 miles?
1 solutions

Answer 446684 by MathLover1(6622) About Me  on 2013-03-25 19:14:08 (Show Source):
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+3 and a half hours is t=3.5h at v=45mph
equal to distance d=157.5+miles
as you know the distance is d=v%2At
plug in given values
d=45%28mil%2Fh%29%2A3.5h
d=45%2A3.5%28mil%2Fcross%28h%29%29%2Across%28h%29
d=157.5mil


Complex_Numbers/730436: IF 1000 YEARS EQUAL A 24 HOUR DAY HOW MUCH WOULD 1 SECOND EQUAL PLESE HELP ME
1 solutions

Answer 446683 by MathLover1(6622) About Me  on 2013-03-25 19:04:01 (Show Source):
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1+day+=+24+hours+=+1440min=86400sec

so, in 1sec you will have 1000%2F86400=0.011574074074074074074074074074074years


But if you want to find out an exact number you must do some research, I might be wrong here, but a year with 1 extra day occurs once every 4th year, so:
1000/4 = 250 this is 250 years with 1 extra day, which changes the math into making us take into account that 250 years of those 1000 has 366 days instead of 365


Or, you can forget leap years and use a more sane representation of years such Julian years (365.25 days, exactly) or tropical years (365.24218967 days at the epoch J2000.0)
365.25%2A24=8766h=31557600sec
so in 1000 years will be 365.25%2A1000=+365250 days
365250+%2F31557600=0.011574074074074074074074074074074


Travel_Word_Problems/730395: how long does it take to drive 750 miles at 55 miles/hour
1 solutions

Answer 446668 by MathLover1(6622) About Me  on 2013-03-25 16:46:12 (Show Source):
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recall the distance formula d=v%2At where d=distance, v=speed and t=time
solve for t
t=d%2Fv
so,to drive d=750mil at v=55%28mil%2Fh%29 will take
t=750mil%2F55%28mil%2Fh%29
t=750cross%28mil%29%2Ah%2F55cross%28mil%29
t=13.64h
t=13h 38min 24sec


Trigonometry-basics/730327: Write the equation of the circle whose center is (-2,-1) and radius is 2(sqrt[3])
1 solutions

Answer 446645 by MathLover1(6622) About Me  on 2013-03-25 14:18:51 (Show Source):
You can put this solution on YOUR website!
Equation of a circle whose center is at (h,k) is:
%28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2....This referrers to the "center-radius form". It may also be referred to as "standard form".
given:
center is at (h,k) = (-2,-1)
and r=2sqrt%283%29
plug given values in formula

%28x-%28-2%29%29%5E2%2B%28y-%28-1%29%29%5E2=%282sqrt%283%29%29%5E2

%28x%2B2%29%5E2%2B%28y%2B1%29%5E2=4%2A3

%28x%2B2%29%5E2%2B%28y%2B1%29%5E2=12




Rational-functions/730160: How do you factor 12+8

1 solutions

Answer 446514 by MathLover1(6622) About Me  on 2013-03-24 23:22:57 (Show Source):
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factor 12%2B8....both 12 and 8 are divisible by 4, so factor out 4
12%2B8=4%283%2B2%29


Circles/730156: how is the steps done for these?
Find the centre and the radius of
1.)25x^2+25y^2=25



1 solutions

Answer 446513 by MathLover1(6622) About Me  on 2013-03-24 23:20:25 (Show Source):
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The center-radius form of the circle equation is in the format %28x-h%29%5E2+%2B+%28y-k%29%5E2+=+r%5E2, with the center being at the point (h, k) and the radius being "r".

25x%5E2%2B25y%5E2=25+....both sides divide by 25

25x%5E2%2F25%2B25y%5E2%2F25=25%2F25+
x%5E2%2By%5E2=1+....compare to %28x-h%29%5E2+%2B+%28y-k%29%5E2+=+r%5E2 and you see that (h, k)=(0, 0) and r=1
+graph%28+600%2C+600%2C+-2%2C+2%2C+-2%2C2%2C+x%5E2%2By%5E2%3C=1%29+


test/730136: Graph the linear equation f(x)=6x
1 solutions

Answer 446511 by MathLover1(6622) About Me  on 2013-03-24 23:11:56 (Show Source):
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Solved by pluggable solver: Graphing Linear Equations
In order to graph y=6%2Ax%2B0 we only need to plug in two points to draw the line

So lets plug in some points

Plug in x=-1

y=6%2A%28-1%29%2B0

y=-6%2B0 Multiply

y=-6 Add

So here's one point (-1,-6)




Now lets find another point

Plug in x=0

y=6%2A%280%29%2B0

y=0%2B0 Multiply

y=0 Add

So here's another point (0,0). Add this to our graph





Now draw a line through these points

So this is the graph of y=6%2Ax%2B0 through the points (-1,-6) and (0,0)


So from the graph we can see that the slope is 6%2F1 (which tells us that in order to go from point to point we have to start at one point and go up 6 units and to the right 1 units to get to the next point) the y-intercept is (0,0)and the x-intercept is (0,0)


We could graph this equation another way. Since b=0 this tells us that the y-intercept (the point where the graph intersects with the y-axis) is (0,0).


So we have one point (0,0)





Now since the slope is 6%2F1, this means that in order to go from point to point we can use the slope to do so. So starting at (0,0), we can go up 6 units



and to the right 1 units to get to our next point


Now draw a line through those points to graph y=6%2Ax%2B0


So this is the graph of y=6%2Ax%2B0 through the points (0,0) and (1,6)


Linear-equations/730137: Someone PLEASE HELP me solve this inequality problem !
~ Graph the inequality x + y is Less than or Equal to 4. Give it in interval
notation.
Thank You !
1 solutions

Answer 446502 by MathLover1(6622) About Me  on 2013-03-24 22:17:03 (Show Source):
You can put this solution on YOUR website!
x+%2B+y+%3C=4

+graph%28+500%2C+500%2C+-10%2C10%2C+-10%2C+10%2C+x+%2B+y+%3C=4%29+
The domain is all real numbers x equal to or smaller than 4, (-infinity, 4]
The range is all real numbers y equal to or smaller than 4, (-infinity, 4]


expressions/730139: 3³ + 4(-1 - 2) - 25
I am having trouble finding the answer. I came up with 3.
1 solutions

Answer 446499 by MathLover1(6622) About Me  on 2013-03-24 22:07:55 (Show Source):


Polynomials-and-rational-expressions/730108: help me to completely factor
5x^3+30x^2+5x+30
1 solutions

Answer 446497 by MathLover1(6622) About Me  on 2013-03-24 22:04:19 (Show Source):


Square-cubic-other-roots/730073: I need an equation that will do the following :
Rationalize a denominator using a cube root and the problem must have a variable before you simplify it. ANSWER must equal 2
1 solutions

Answer 446471 by MathLover1(6622) About Me  on 2013-03-24 21:05:13 (Show Source):


Linear-systems/730051: Please HELP me solve this quesion !!!
A line passes through the points (2,9) and (9,2) ~
a. Write the equation of the line.
b. Write the equation of the parallel line going through the origin.
c. Write the equation of the perpendicular line through (2,9).
1 solutions

Answer 446427 by MathLover1(6622) About Me  on 2013-03-24 19:17:09 (Show Source):
You can put this solution on YOUR website!

a.
the equation of the line passes through the points (2,9) and (9,2)

Solved by pluggable solver: FIND EQUATION of straight line given 2 points
hahaWe are trying to find equation of form y=ax+b, where a is slope, and b is intercept, which passes through points (x1, y1) = (2, 9) and (x2, y2) = (9, 2).
Slope a is a+=+%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29+=+%282-9%29%2F%289-2%29+=+-1.
Intercept is found from equation a%2Ax%5B1%5D%2Bb+=+y%5B1%5D, or -1%2A2+%2Bb+=+11. From that,
intercept b is b=y%5B1%5D-a%2Ax%5B1%5D, or b=9--1%2A2+=+11.

y=(-1)x + (11)

Your graph:





b.

the equation of the parallel to line y=-1x%2B11 going through the origin (0,0)

Solved by pluggable solver: Finding the Equation of a Line Parallel or Perpendicular to a Given Line


Since any two parallel lines have the same slope we know the slope of the unknown line is -1 (its from the slope of y=-1%2Ax%2B11 which is also -1). Also since the unknown line goes through (0,0), we can find the equation by plugging in this info into the point-slope formula

Point-Slope Formula:

y-y%5B1%5D=m%28x-x%5B1%5D%29 where m is the slope and (x%5B1%5D,y%5B1%5D) is the given point



y-0=-1%2A%28x-0%29 Plug in m=-1, x%5B1%5D=0, and y%5B1%5D=0



y-0=-1%2Ax%2B%281%29%280%29 Distribute -1



y-0=-1%2Ax-0 Multiply



y=-1%2Ax-0%2B0Add 0 to both sides to isolate y

y=-1%2Ax%2B0 Combine like terms

So the equation of the line that is parallel to y=-1%2Ax%2B11 and goes through (0,0) is y=-1%2Ax%2B0


So here are the graphs of the equations y=-1%2Ax%2B11 and y=-1%2Ax%2B0



graph of the given equation y=-1%2Ax%2B11 (red) and graph of the line y=-1%2Ax%2B0(green) that is parallel to the given graph and goes through (0,0)





c.
the equation of the perpendicular to line y=-1x%2B11 through (2,9)
Solved by pluggable solver: Finding the Equation of a Line Parallel or Perpendicular to a Given Line


Remember, any two perpendicular lines are negative reciprocals of each other. So if you're given the slope of -1, you can find the perpendicular slope by this formula:

m%5Bp%5D=-1%2Fm where m%5Bp%5D is the perpendicular slope


m%5Bp%5D=-1%2F%28-1%2F1%29 So plug in the given slope to find the perpendicular slope



m%5Bp%5D=%28-1%2F1%29%281%2F-1%29 When you divide fractions, you multiply the first fraction (which is really 1%2F1) by the reciprocal of the second



m%5Bp%5D=1%2F1 Multiply the fractions.


So the perpendicular slope is 1



So now we know the slope of the unknown line is 1 (its the negative reciprocal of -1 from the line y=-1%2Ax%2B11). Also since the unknown line goes through (2,9), we can find the equation by plugging in this info into the point-slope formula

Point-Slope Formula:

y-y%5B1%5D=m%28x-x%5B1%5D%29 where m is the slope and (x%5B1%5D,y%5B1%5D) is the given point



y-9=1%2A%28x-2%29 Plug in m=1, x%5B1%5D=2, and y%5B1%5D=9



y-9=1%2Ax-%281%29%282%29 Distribute 1



y-9=1%2Ax-2 Multiply



y=1%2Ax-2%2B9Add 9 to both sides to isolate y

y=1%2Ax%2B7 Combine like terms

So the equation of the line that is perpendicular to y=-1%2Ax%2B11 and goes through (2,9) is y=1%2Ax%2B7


So here are the graphs of the equations y=-1%2Ax%2B11 and y=1%2Ax%2B7




graph of the given equation y=-1%2Ax%2B11 (red) and graph of the line y=1%2Ax%2B7(green) that is perpendicular to the given graph and goes through (2,9)





y=-1x%2B11...given line
y=-1x...parallel line
y=x%2B7...perpendicular

let's graph them all together:
+graph%28+600%2C+600%2C+-15%2C+15%2C+-15%2C+15%2C+-1x%2B11%2C-1x%2Cx%2B7%29+


Quadratic_Equations/730045: how do you change 3(x+1.33333333333333)(x+7) to a fractional coefficient
1 solutions

Answer 446425 by MathLover1(6622) About Me  on 2013-03-24 19:05:20 (Show Source):
You can put this solution on YOUR website!

+3%28x%2B1.33333333333333%29%28x%2B7%29.....1.33333333333333 as a fraction is 4%2F3
+3%28x%2B4%2F3%29%28x%2B7%29
+%283x%2B12%2F3%29%28x%2B7%29
+3x%5E2%2B7x%2B%2812%2F3%29x%2B7%2812%2F3%29
+3x%5E2%2B7x%2B12x%2F3%2B84%2F3
+3%2A3x%5E2%2F3%2B3%2A7x%2F3%2B12x%2F3%2B84%2F3
+9x%5E2%2F3%2B21x%2F3%2B12x%2F3%2B84%2F3
+9x%5E2%2F3%2B33x%2F3%2B84%2F3
+%289%2F3%29x%5E2%2B%2833%2F3%29x%2B84%2F3




Complex_Numbers/730030: simplify. Write the result in the form a+bi (2+ 3i)(5-3i)(-7+ i)
1 solutions

Answer 446411 by MathLover1(6622) About Me  on 2013-03-24 18:38:54 (Show Source):


Polynomials-and-rational-expressions/730026: Simplify the rational expression
9x^2-15x+25
___________
27x^3+125
1 solutions

Answer 446402 by MathLover1(6622) About Me  on 2013-03-24 18:31:12 (Show Source):


Triangles/730033: What type of triangle has the side lengths of 2,3,4 ?
What type of triangle has the side lengths of 2,3,5 ?
What type of triangle has the side lengths of 6,8,9 ?
What type of triangle has the side lengths of 6,8,10 ?
1 solutions

Answer 446397 by MathLover1(6622) About Me  on 2013-03-24 18:20:22 (Show Source):
You can put this solution on YOUR website!
By the number of equal sides they have:
scalene - all 3 sides have different lengths
isosceles - 2 sides have equal lengths
equilateral - all 3 sides are equal

type of triangle has the side lengths of 2,3,4 is scalene triangle
type of triangle has the side lengths of 2,3,5is scalene triangle
type of triangle has the side lengths of 6,8,9 is scalene triangle
What type of triangle has the side lengths of 6,8,10 is scalene triangle


logarithm/729881: Let x = log6 2. Express log6 18 in terms of x.
1 solutions

Answer 446384 by MathLover1(6622) About Me  on 2013-03-24 17:47:58 (Show Source):
You can put this solution on YOUR website!
Let x+=+log%286%2C+%282%29%29.
Express log%286%2C%2818%29%29 in terms of x.