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15390..15419 , 15420..15449 , 15450..15479 , 15480..15509 , 15510..15539 , 15540..15569 , 15570..15599 , 15600..15629 , 15630..15659, >>Nexttest/404312: 4x-y=7. What is the slope intercept of that equation 1 solutions
Answer 285802 by ankor@dixie-net.com(15661) on 2011-02-04 19:34:36 (Show Source):
You can put this solution on YOUR website!4x-y=7. What is the slope intercept of that equation
:
The slope/intercept form y = mx + b where m is the slope, and b is the y intercept
4x - y = 7
Subtract 4x from both sides
-y = -4x + 7
y has to be positive, multiply by -1
y = 4x - 7
|
expressions/404299: Archimedes discovered that if an object, that is more dense than water, is submerged in water then an amount of water equal to the volume of the object is displaced by that object. A rectangler tank 4 feet is filled to a depth of 3 feet with water. A sphere with a diameter of 3 feet is immersed in the tank. How much does the water rise in the tank? 1 solutions
Answer 285801 by ankor@dixie-net.com(15661) on 2011-02-04 19:29:39 (Show Source):
You can put this solution on YOUR website!Archimedes discovered that if an object, that is more dense than water, is
submerged in water then an amount of water equal to the volume of the object
is displaced by that object.
A rectangular tank 4 feet is filled to a depth of 3 feet with water.
A sphere with a diameter of 3 feet is immersed in the tank.
How much does the water rise in the tank?
:
Let x = amt (in feet) the water rises
:
Regarding the tank: assume the width is 3.5 ft to accommodate the sphere:
The tank is 4 by 3.5
:
Find the vol of the sphere (r = 1.5 ft)
V = 
V = 
V = 14.137 cu/ft
:
Find the amt of rise in the water
4 * 3.5 * x = 14.137
14x = 14.137
x = 
x = 1.01 ft
|
Quadratic_Equations/404199: a wire of length 100 cm is cut into two piece and each part is bent to form a square. if the sum of the areas of the two square is 425 cm^2 find the lenghts of the sides of the two squares 1 solutions
Answer 285790 by ankor@dixie-net.com(15661) on 2011-02-04 18:44:05 (Show Source):
You can put this solution on YOUR website!a wire of length 100 cm is cut into two piece and each part is bent to form a square.
if the sum of the areas of the two square is 425 cm^2 find the lengths of the sides of the two squares
:
Let x = side of one square
Let y = side of the other square
then
4x + 4y = 100
simplify, divide by 4
x + y = 25
y = (25-x), use this for substitution
and
x^2 + y^2 = 425
Substitute (25-x) for y
x^2 + (25-x)^2 = 425
FOIL (25-x)(25-x)
x^2 + 625 - 50x + x^2 = 425
Arrange as a quadratic equation
x^2 + x^2 - 50x + 625 - 425 = 0
2x^2 - 50x + 200 = 0
(x-20)(2x-10) = 0
Two solutions
x = 20 is the side of one square
or
2x = 10
x = 5 is the side of one square
:
Find y
25 - 20 = 5 is the side of the other square
or
25 - 5 = 20 is the side of the other square
:
anyway, one square side is 20, the other square side is 5
:
:
See if this is true
4(20) + 4(5) =
80 + 20 = 100
and
20^2 + 5^2 = 425
|
Signed-numbers/404423: 1/3x=3x-9
i am a grandmother trying to help my grandchild. Although I aced algebra in high school, that was over half century ago. i having been trying for days with the help of the internet and textbooks and just can't figure out how to do this simple math. maybe you can help. please show steps. 1 solutions
Answer 285778 by ankor@dixie-net.com(15661) on 2011-02-04 17:50:21 (Show Source):
You can put this solution on YOUR website! x = 3x - 9
Multiply both sides by 3 to get rid of the denominators
1x = 9x - 27
+27 = 9x - x
27 = 8x
x = 
x = 3  or 3.375
:
:
Check solution in original problem
 *  = 3x - 9
cancel 3 into 27
 = 3*  -9
 =  - 9
 =  -  ; confirms our solution
|
Travel_Word_Problems/404271: Distance and time: Two athletes are jogging in the same direction along an exercise path. After x minutes the first athletes distance in miles from a parking lot is given by 1/6x and the second athletes distance is given by 1/8x + 2.
(a) When are the athletes the same distance from the parking lot?
(b) When is the first athlete farther away from the parking lot than the second?
1 solutions
Answer 285763 by ankor@dixie-net.com(15661) on 2011-02-04 16:11:07 (Show Source):
You can put this solution on YOUR website!Two athletes are jogging in the same direction along an exercise path.
After x minutes the first athletes distance in miles from a parking lot is
given by  x and the second athletes distance is given by  x + 2.
:
(a) When are the athletes the same distance from the parking lot?
 x =  x + 2
 x -  x = 2
Common denominator is 24
 x -  x = 2
 x = 2
Multiply both sides by 24
1x = 24(2)
x = 48 minutes
:
We can check this:
 (48) =  (48) + 2
:
:
(b) When is the first athlete farther away from the parking lot than the second?
 x > 2
x > 48 minutes, Say 49 minutes
 (49) = 8.167 mi
 (49) + 2 = 8.125 mi
|
Linear-systems/404340: I am having serious problem trying to solve by elimination method
7x-8y=-41
8x+7y=50
Soution set is
Thank you for your help. 1 solutions
Answer 285758 by ankor@dixie-net.com(15661) on 2011-02-04 15:34:06 (Show Source):
You can put this solution on YOUR website!I am having serious problem trying to solve by elimination method
7x - 8y = -41
8x + 7y = 50
:
We need to get the coefficient of one of the variables (x or Y) to be the same value.
We will do this to y, then we can add the equations
:
multiply the 1st equation by 7, multiply the 2nd equation by 8; results
49x - 56y = -287
64x + 56y = 400
------------------adding eliminates y, find x
113x + 0 = 113
x = 
x = 1
:
Find y using the 2nd original equation
8 + 7y = 50
7y = 50 - 8
7y = 42
y = 
y = 6
:
:
Check solution in the 1st original equation
7x - 8y = -41
7(1) - 8(6) = -41
7 - 48 = 41; confirms our solutions of x = 1, y = 6
:
:
did this clear up some of the trouble you are having with these problems?
|
Linear-equations/404232: how would you solve 2x=7y-17
5y=17-3x 1 solutions
Answer 285757 by ankor@dixie-net.com(15661) on 2011-02-04 15:23:03 (Show Source):
You can put this solution on YOUR website!how would you solve
2x = 7y - 17
5y = 17 - 3x
:
Rearrange to standard form, and use elimination:
2x - 7y = -17
3x + 5y = 17
:
Multiply the 1st equation by -3, the 2nd equation by 2, results:
-6x + 21y = 51
+6x + 10y = 34
------------------Adding eliminates x find y
31y = 85
y =  , an awful number
:
Find x using the 1st original equation
2x = 7y - 17
2x = 7(  ) - 17
2x = (  ) - 
2x = 
Divide both sides by 2
x =  ; another awful number
:
:
Check this using decimals in the 2nd original equation
 = 2.742
 = 1.097
:
3x + 5y = 17
3(1.097) + 5(2.742) =
3.291 + 13.71 = 17.00; confirms our awful solutions for x and y
|
Polynomials-and-rational-expressions/404141: Divide and simplify...I have worked this problem and I'm not sure if I have done it correctly. r^2+5r/r^2+4r-5 divided by r/r+1 I came up with r+1/r-1 for an answer. Am I on the right track?
(r^2+5r)(r+1)=(r+5)(r+1)=r+1*x(x+5)
(r^2+4r-5)=(r+5)(r-1)r=r-1*x(x-5)
I have gotten confused and need to know if I am on track. Thanks! 1 solutions
Answer 285750 by ankor@dixie-net.com(15661) on 2011-02-04 13:35:32 (Show Source):
You can put this solution on YOUR website!
Let's see, we will go thru it step-by-step
:
Invert the dividing fraction and multiply
 * 
:
Factor
 * 
:
Cancel (r+5) and r, leaving
 *  =  ; so you're absolutely right, way to go.
:
:
But I am not sure about, what's meant here;
(r^2+5r)(r+1)=(r+5)(r+1)=r+1*x(x+5)
(r^2+4r-5)=(r+5)(r-1)r=r-1*x(x-5)
:
How did x get in there?
|
Surface-area/404193: PLS. HELP ME SOLVE THIS PROBLEM.. THANK YOU SO MUCH.
FIND THE AREA OF A TRIANGLE WHOSE VERTEX IS AT THE MIDPOINT OF AN UPPER EDGE OF A CUBE OF EDGE A, AND WHOSE BASE MEET WITH DIAGONALLY OPPOSITE EDGE OF A CUBE. 1 solutions
Answer 285713 by ankor@dixie-net.com(15661) on 2011-02-04 11:26:55 (Show Source):
You can put this solution on YOUR website! FIND THE AREA OF A TRIANGLE WHOSE VERTEX IS AT THE MIDPOINT OF AN UPPER EDGE OF A CUBE OF EDGE A,
AND WHOSE BASE MEET WITH DIAGONALLY OPPOSITE EDGE OF A CUBE.
:
The base will also be A
:
The height will = the diagonal inside the cube
h = 
Area of triangle =  * A *
|
Travel_Word_Problems/404102: Going down the river a boat went 11 mph. Going up the river it only went 3 mph. What is the speed of the current? How fast would the boat go if there were no current? 1 solutions
Answer 285705 by ankor@dixie-net.com(15661) on 2011-02-04 10:51:11 (Show Source):
You can put this solution on YOUR website!Going down the river a boat went 11 mph.
Going up the river it only went 3 mph. What is the speed of the current? How fast would the boat go if there were no current?
:
Let s = speed in still water
Let c = speed of the current
:
Two equations, use elimination here
s + c = 11
s - c = 3
---------------Addition eliminates c find s
2s = 14
s = 7 mph in still water
|
Geometry_Word_Problems/403986: A wire 310 in. long is cut into two pieces. One piece is formed into a square and the other into a circle. If the two figures have the same area, what are the lengths of the two pieces of wire (to the nearest tenth of an inch)? 1 solutions
Answer 285638 by ankor@dixie-net.com(15661) on 2011-02-03 21:45:55 (Show Source):
You can put this solution on YOUR website!A wire 310 in. long is cut into two pieces. One piece is formed into a square and the other into a circle.
If the two figures have the same area, what are the lengths of the two pieces of wire (to the nearest tenth of an inch)?
:
Let s = the side of the square
then
4s = the perimeter of the square
s^2 = the area of the square
:
Let r = the radius of the circle
then
 = the circumference of the circle
 = area of the circle
:
"the two figures have the same area,
s^2 = 
s =
:
"A wire 310 in. long is cut into two pieces."
:
Perimeter + Circumference = 310 inches
4s +  = 310
:
Replace s with
 = 310
:
simplify, divide by 2, Extract r
 = 155
:
Change pi to decimal values
2r(1.772) + r(3.1416) = 155
3.545r + 3.1416r = 155
6.6865r = 155
r = 
r = 23.18
:
Find the circumference
C = 
C = 145.7 inches the length of the wire to make the circle
then
310 - 145.7 = 164.3 inches is the length to make the square
:
:
Check this by finding the area of circle and the square
Square: (164.3/4)^2 = 1687.155 sq/inches
Circle:  = 1688.0 sq/inches, discrepancy is from rounding off
|
Linear_Equations_And_Systems_Word_Problems/403981: A water flow restrictor has reduced the flow of water to 2 gal/min. This amount is 1 gal/min less than three-fifths the original flow rate. Find the original rate. 1 solutions
Answer 285559 by ankor@dixie-net.com(15661) on 2011-02-03 18:02:13 (Show Source):
You can put this solution on YOUR website!A water flow restrictor has reduced the flow of water to 2 gal/min.
This amount is 1 gal/min less than three-fifths the original flow rate.
Find the original rate.
:
Let r = the original rate of flow
:
 r - 1 = 2
 r = 2 + 1
 r = 3
Multiply both sides by 5
3r = 5(3)
3r = 15
r = 
r = 5 gal/min was the original flow
|
Complex_Numbers/403927: Find all solutions of the equation x^2+x+1=0 and express them in the form a+bi. 1 solutions
Answer 285540 by ankor@dixie-net.com(15661) on 2011-02-03 17:06:38 (Show Source):
You can put this solution on YOUR website!Find all solutions of the equation: x^2 + x + 1 = 0
Solve this using the completing square method
x^2 + x + ___ = -1
Divide the coefficient of x by 2 and square it(1/2)^2, add to both sides
x^2 + x + .25 = - 1 + .25
:
x^2 + x + .25 = -.75
:
(x+.5)^2 = -.75
:
x + .5 = +/- 
:
x + .5 = +/- 
:
x = 
And
x =
|
Volume/403856: My question is how do you find the total volume for a solid with the help of algebra. for example a square pyramid and all the measurements just equal to m. how exactly do i do it 1 solutions
Answer 285530 by ankor@dixie-net.com(15661) on 2011-02-03 16:29:35 (Show Source):
You can put this solution on YOUR website!My question is how do you find the total volume for a solid with the help of algebra. for example a square pyramid and all the measurements just equal to m. how exactly do i do it
:
The volume of a square pyramid: A =  b^2*h
If the base and the h = m then
A =  m^3
|
Linear-systems/403846: I have a problem that I can't seem to be able to set up. It is Pablo is 3 miles behind Marc. Pablo increases his speed to 5 miles per hour, while Marc, runs at 4mph. At this rate, how many miles will Pablo have to run to catch up to Marc? How long will it take? 1 solutions
Answer 285515 by ankor@dixie-net.com(15661) on 2011-02-03 15:50:53 (Show Source):
You can put this solution on YOUR website!Pablo is 3 miles behind Marc.
Pablo increases his speed to 5 miles per hour, while Marc, runs at 4mph.
At this rate, how many miles will Pablo have to run to catch up to Marc?
How long will it take?
:
Let t = time for P to catch M
P has to run 3 more miles than M
Write a distance equation; dist = speed * time
5t = 4t + 3
5t - 4t = 3
t = 3 hrs for P to catch M
:
How many miles will P have to run to catch M
3 * 5 = 15 miles
:
:
Check this, find the distance each runs
5*3 = 15 mi
4*3 = 12 mi
------------
diff: 3 mi
|
Miscellaneous_Word_Problems/403805: Betsy, a recent retiree, requires $6,000 per year in extra income. She has $60,000 to invest and can invest in B-rated bonds paying 15% per year or in a certificate of deposit (CD) paying 5% per year. How much money should be invested in each to realize exactly $6,000 in interest per year? 1 solutions
Answer 285507 by ankor@dixie-net.com(15661) on 2011-02-03 15:32:56 (Show Source):
You can put this solution on YOUR website!requires $6,000 per year in extra income.
She has $60,000 to invest and can invest in B-rated bonds paying 15% per year
or in a certificate of deposit (CD) paying 5% per year.
How much money should be invested in each to realize exactly $6,000 in interest per year?
:
Let b = amt to be invested in bonds
Let c = amt in CD's
:
b + c = 60000
c = (60000-b)
:
.15b + .05c = 6000
replace c with (60000-b)
.15b + .05(60000-b) = 6000
.15b + 3000 - .05b = 6000
.15b - .05b = 6000 - 3000
.10b = 3000
b = 
b = $30,000 invested in bonds
and
c = 60000 - 30000
c = $30,000 invested in CD's
:
;
See if that checks out
.15(30000) = 4500
.05(30000) = 1500
------------------
total amt: 6000
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Mixture_Word_Problems/403826: A 20 gallon solution contains 50% salt. How much pure water needs to be added in it to get a solution that contains 30% salt? 1 solutions
Answer 285488 by ankor@dixie-net.com(15661) on 2011-02-03 13:01:16 (Show Source):
You can put this solution on YOUR website!A 20 gallon solution contains 50% salt.
How much pure water needs to be added in it to get a solution that contains 30% salt?
:
Let w = amt of water required
The actual amt of salt will stay the same, only the percent changes
.50(20) = .30(w + 20)
10 = .3w + 6
10 - 6 = .3w
s = 
w = 13  gal of pure water to be added
:
:
Check for amt of salt: .3(13.333 + 20) = 10
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Linear-equations/403694: Mark is three times as old as Luke. In 5 years Mark will be two times as old as Luke is in 5 years. How old is each one now?
Svetlana is four times as old as Boris. In 10 years Svetlana will be three times as old as Boris is in 10 years. How old is each one now?
Masato is twice as old as Kim. Ten years ago, Masato was three times as old as Kim was ten years ago. How old is each one now? 1 solutions
Answer 285464 by ankor@dixie-net.com(15661) on 2011-02-03 09:51:24 (Show Source):
You can put this solution on YOUR website!Mark is three times as old as Luke. In 5 years Mark will be two times as old as Luke is in 5 years.
How old is each one now?
:
let m = Mark's present age
Let L = Luke's
Write an equation for each statement
:
"Mark is three times as old as Luke."
m = 3L
:
"In 5 years Mark will be two times as old as Luke is in 5 years."
m + 5 = 2(L+5)
m + 5 = 2L + 10
m = 2L + 10 - 5
m = 2L + 5
From the 1st statement, replace m with 3L
3L = 2L + 5
3L - 2L = 5
L = 5 yrs is Luke's present age
then
m = 3(5)
m = 15 yrs is Mark's present age
:
Confirm this in the statement
""In 5 years Mark will be two times as old as Luke is in 5 years."
15 + 5 = 2(5 + 5);
:
:
You can do these other two problems in the same way,
:
"Svetlana is four times as old as Boris."
s = 4b
:
"In 10 years Svetlana will be three times as old as Boris is in 10 years."
s + 10 = 3(b+10)
How old is each one now?
:
:
See if you can do this one completely on your own, difficulty? ankor@att.net
:
Masato is twice as old as Kim. Ten years ago, Masato was three times as old as Kim was ten years ago.
How old is each one now?
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absolute-value/403676: a certain gas will escape from a storage tank according to the formula e=180√(p), where e represents the amount escaping per minute in gallons, and p represents the pressure in pounds per square inch. What is the pressure on the gas when about 225 gallons per minute are escaping?Round your answer to the nearest tenth. 1 solutions
Answer 285461 by ankor@dixie-net.com(15661) on 2011-02-03 09:38:26 (Show Source):
You can put this solution on YOUR website!a certain gas will escape from a storage tank according to the formula e=180√(p),
where e represents the amount escaping per minute in gallons, and p represents
the pressure in pounds per square inch.
What is the pressure on the gas when about 225 gallons per minute are escaping?
:
Replacing e with 225, we have
 = 225
divide both sides by 180
 =
 = 1.25
square both sides
p = 
p = 1.5625 psi
:
:
Check this on a calc: enter  results: 225
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Travel_Word_Problems/403672: A passenger jet travels from Los Angeles to Bombay, India, in 22h. The return flight takes 17 h. The difference in flight times is caused by winds over the Pacific Ocean that blow primarily from west to east. If the jet's average speed in still air is 550 mi/h what is the average speed of the wind during the round trip flight? Round to the nearest mile per hour. Is your answer reasonable? 1 solutions
Answer 285456 by ankor@dixie-net.com(15661) on 2011-02-03 09:30:35 (Show Source):
You can put this solution on YOUR website!A passenger jet travels from Los Angeles to Bombay, India, in 22h.
The return flight takes 17 h.
The difference in flight times is caused by winds over the Pacific Ocean that
blow primarily from west to east.
If the jet's average speed in still air is 550 mi/h what is the average speed
of the wind during the round trip flight? Round to the nearest mile per hour.
Is your answer reasonable?
:
Let w = speed of the wind
:
Write a distance equation (dist is the same both ways
17(550+w) = 22(550-w)
9350 + 17w = 12100 - 22w
17w + 22w = 12100 - 9350
39w = 2750
w = 
w = 70.5 mph seems very reasonable
:
:
Check solution by finding the distances using these value
17(550+70.5) = 10549 mi
22(550-70.5) = 10549 mi; confirms our solution of w = 70.5 mph
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Evaluation_Word_Problems/403635: A gardener wants to create a rectangular garden with length of 3x - 3y ft. and width of x - 5y ft. What is an algebraic expression for the area of the garden? Be sure to multiply this out, express in simplest correct mathematical form, and include units. 1 solutions
Answer 285387 by ankor@dixie-net.com(15661) on 2011-02-02 21:43:44 (Show Source):
You can put this solution on YOUR website!A gardener wants to create a rectangular garden with length of 3x - 3y ft. and width of x - 5y ft. What is an algebraic expression for the area of the garden?
:
A = (3x - 3y)*(x - 5y)
FOIL
A = 3x^2 - 15xy - 3xy + 15y^2
Add like terms
A = 3x^2 - 18xy + 15y^2
Factor out 3
A = 3(x^2 - 6xy + 5y^2)
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Miscellaneous_Word_Problems/403330: A person wishes to tile a kitchen floor with square tiles 8 inches on a side. if the kitchen measures 10 ft by 12 ft,how many tiles are needed? 1 solutions
Answer 285378 by ankor@dixie-net.com(15661) on 2011-02-02 21:11:38 (Show Source):
You can put this solution on YOUR website!A person wishes to tile a kitchen floor with square tiles 8 inches on a side.
if the kitchen measures 10 ft by 12 ft,how many tiles are needed?
:
Find the area of the floor in square inches:
10 * 12 * 144 = 17280 sq/inches
:
Find the area of each tile:
8*8 = 64 sq/inches
:
Find the number required
 = 270 tiles
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Circles/403639: in a circle, a chord 14 units long is drawn 3 units from the center of the origin. what is the length of the radius to the nearest 10th 1 solutions
Answer 285376 by ankor@dixie-net.com(15661) on 2011-02-02 21:01:04 (Show Source):
You can put this solution on YOUR website!in a circle, a chord 14 units long is drawn 3 units from the center of the origin.
what is the length of the radius to the nearest 10th
:
If you draw this out, you can see that the chord, two radii from the ends of the
chord and line from the midpoint of chord to the center, form two right angle
triangles, the radii are the hypotenuses
:
r^2 = 7^2 + 3^2
r^2 = 49 + 9
r = 
r = 7.6 units
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Travel_Word_Problems/403524: billy and miranda are training at the track. billy can complete a lap in 40 seconds. miranda and billy begin at the same start/finish line and at the same time, but run in opposite directions. Although different, their individual speeds remain constant and they pass each other every 15 seconds. miranda stops after finishing 12 laps. billy continues to run at the same rate.
-my task is to determine how many times miranda and billy passed each other exactly at the start/finish line during the time they were both running and how many more minutes and seconds and exactly how many morelaps billy will need to run to have run exactly the same distance that miranda ran.
*i tried to draw a diagram and i had miranda run the 12 laps and during those 12 laps i marked evert 15 seconds where they met, however i got diferent answers everytime i tried. 1 solutions
Answer 285361 by ankor@dixie-net.com(15661) on 2011-02-02 20:07:43 (Show Source):
You can put this solution on YOUR website!billy can complete a lap in 40 seconds.
miranda and billy begin at the same start/finish line and at the same time,
but run in opposite directions.
Although different, their individual speeds remain constant and they pass each other every 15 seconds.
miranda stops after finishing 12 laps.
billy continues to run at the same rate.
-my task is to determine how many times miranda and billy passed each other
exactly at the start/finish line during the time they were both running and
how many more minutes and seconds and exactly how many more laps billy will
need to run to have run exactly the same distance that miranda ran.
:
Find out how long it takes M to complete one lap
After 15 sec, B completes  or  of one lap
therefore M has completed  of one lap when the they meet in 15 sec
B to M speed ratio= 3:5
Time is inversely proportional to speed, let m = M's lap time
 = 
Cross multiply
5m = 5*40
m = 120/5
m = 24 sec for M to complete one lap
:
M completes 12 laps: 24 * 12 = 288 sec
B completes 12 laps: 40 * 12 = 480 sec
B runs; 480 - 288 = 192 sec longer than M to complete 12 laps
:
How many times will they meet during the 288 sec that M ran?
They met every 15 sec: 288/15 ~ 19 times
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test/403481: when the reciprocal of three times a number is subtracted from the reciprocal of the subtracted from the reciprocal of thnumber, the results is one sixth.find the number 1 solutions
Answer 285315 by ankor@dixie-net.com(15661) on 2011-02-02 16:29:06 (Show Source):
You can put this solution on YOUR website!when the reciprocal of three times a number is subtracted from the reciprocal of
the subtracted from the reciprocal of the number,
the results is one sixth.find the number
:
Rewrite this so it makes sense.
"when the reciprocal of three times a number is subtracted from the reciprocal of the number, the results is one sixth." find the number.
:
Let x = the number
 -  = 
Multiply by 6x
6x*  - 6x  = 6x 
cancel the denominators and you have:
6 - 6(3) = x
6 - 18 = x
-12 = x
the number is -12
:
:
See if that's true
 -  =
Minus a minus is a plus
 +  =
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Rectangles/403311: the length of each side of a square is 5 in more than the length of each side of a smaller square. the difference of the areas of the squares is 95in squared. find the lengths of the sides of the two squares 1 solutions
Answer 285308 by ankor@dixie-net.com(15661) on 2011-02-02 16:12:20 (Show Source):
You can put this solution on YOUR website!the length of each side of a square is 5 in more than the length of each side of a smaller square.
the difference of the areas of the squares is 95in squared.
find the lengths of the sides of the two squares
:
Let x = side of the smaller square
then
x^2 = area of the smaller square
and
(x+5) = side of the larger square
then
(x+5)^2 = area of the larger square
FOIL this, subtract the smaller square area
x^2 + 10x + 25 - x^2 = 95
x^2 - x^2 + 10x = 95 - 25
10x = 70
x = 7 inches is the side of the smaller square
then
7 + 5 = 12 inches is the side of the larger square
:
:
Check this by finding the areas
12^2 - 7^2
144 - 49 = 95; confirms our solutions
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Polygons/403301: Robert has a rectangular garden that is currently 195 ft^2 and has the perimeter of 56 ft. He wants to increase the size of his garden by 4 ft in both directions. What will be the area of his expanded garden? 1 solutions
Answer 285305 by ankor@dixie-net.com(15661) on 2011-02-02 16:04:06 (Show Source):
You can put this solution on YOUR website!Robert has a rectangular garden that is currently 195 ft^2 and has the perimeter of 56 ft.
He wants to increase the size of his garden by 4 ft in both directions. What will be the area of his expanded garden?
:
Find the dimensions of the original garden
2L + 2W = 56
Divide by 2
L + W = 28
L = (28-W)
:
L*W = 195
(28-W) * W = 195
Arrange as a quadratic equation
-W^2 + 28W - 195 = 0
Multiply by -1
W^2 - 28W + 195 = 0
Factor this to:
(W-15)(W-13) = 0
two solutions
W = 13 then L = 15
W = 15 then L = 13
anyway the rectangle is 15 by 13
:
Add 4 ft to each dimension
19 * 17 = 323 sq/ft is the area of the expanded garden
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Travel_Word_Problems/403237: if i run 100 Meters in 12.0 seconds, how long would it take me to run 2 miles? 1 solutions
Answer 285277 by ankor@dixie-net.com(15661) on 2011-02-02 14:47:39 (Show Source):
You can put this solution on YOUR website!if i run 100 Meters in 12.0 seconds, how long would it take me to run 2 miles?
Find your speed in meters/sec:  = 8.3333 m/sec
convert to ft/sec: 8.3333 * 3.281 = 27.341 ft/sec
convert 2 miles to ft: 2 * 5280 = 10650 ft
Find the time at this speed:  = 386.2 seconds or 6 min 26.2 seconds
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