The area of a rectangle is 72 square inches. If the length is 40 inches greater than four times the width. What are the dimensions of the rectangle. I need one variable in the equation!

Question

anonymous · Answer

I need help with this problem please someone help me.

campbell_st · Answer

let the width be x 

the length is 4x + 40

the area x(4x + 40) = 72

expand and simplify

4x^2 + 40x - 72 = 0

4(x^2 + 10x - 18) = 0

use the general quadratic formula to solve... and only consider the positive value for x as distance can only be positive

anonymous · Answer

Solve the following for L and w:
{ L w = 72, L = 40 + 4 w }$$\left\{L=4 \left(5+\sqrt{43}\right),w=-5+\sqrt{43}\right\} $$