SOLUTION: A concrete driveway is 5 feet longer than twice its width. It has a brick walkway 3 feet wide on the front and side of the driveway. The area of the brick walkway is 213 square fee
Algebra ->
Customizable Word Problem Solvers
-> Geometry
-> SOLUTION: A concrete driveway is 5 feet longer than twice its width. It has a brick walkway 3 feet wide on the front and side of the driveway. The area of the brick walkway is 213 square fee
Log On
Question 588320: A concrete driveway is 5 feet longer than twice its width. It has a brick walkway 3 feet wide on the front and side of the driveway. The area of the brick walkway is 213 square feet. Find the dimensions of the driveway. Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! A concrete driveway is 5 feet longer than twice its width.
It has a brick walkway 3 feet wide on the front and side of the driveway.
The area of the brick walkway is 213 square feet.
Find the dimensions of the driveway.
:
Let x = width of the driveway
then
(2x+5) = length of the drive way
:
3' walkway on two sides, adds 5 ft to each driveway dimension
(x+3) = overall width
(2x+8) = overall length
:
An area equation
:
Overall area - driveway area = walkway area
(x+3)(2x+8) - x(2x+5) = 213
FOIL
(2x^2 + 8x + 6x + 24) - (2x^2 + 5x) = 213
2x^2 + 14x + 24 - 2x^2 - 5x = 213
Combine like terms
2x^2 - 2x^2 + 14x - 5x = 213 - 24
9x = 189
x = 189/9
x = 21 ft is the width of the driveway
then
2(21) + 5 = 47 ft is the length of the driveway
:
:
See of this checks out, find the overall area and driveway area
(21+3)*(47+3) = 1200
d.way: 21 * 47 = 987
---------------------
walkway area; = 213
