SOLUTION: A concrete driveway has a perimeter of 280 feet. The length of the driveway is 20 feet more than 4 times its width. Find the length and width of the driveway by writing two equati

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A concrete driveway has a perimeter of 280 feet. The length of the driveway is 20 feet more than 4 times its width. Find the length and width of the driveway by writing two equati      Log On


   



Question 103969: A concrete driveway has a perimeter of 280 feet. The length of the driveway is 20 feet more than 4 times its width. Find the length and width of the driveway by writing two equations with two variables, and solving the equations by either the addition method or the substitution method.
To get credit, you must define the variables, create two equations, then solve those two equations using algebraic methods of addition or substitution.

Answer by elima(1433) About Me  (Show Source):
You can put this solution on YOUR website!
A concrete driveway has a perimeter of 280 feet. The length of the driveway is 20 feet more than 4 times its width. Find the length and width of the driveway by writing two equations with two variables, and solving the equations by either the addition method or the substitution method.
L=length
W=width
2W+2L=280
L=4W+20
I will use the substitution method;
2W+2(4W+20)=280
2W+8W+40=280
10W=240
W=24
Now plug that into either equation for W;
2(24)+2L=280
48+2L=280
2L=232
L=116
:)