Question

A rectangle has an area of 72 square units. The width of the rectangle is 9 units. The length of the rectangle is 2x + 4. What is the rectangle's length?

Answer 1

So you want to setup an equation with the information you have:

l x w = A

l = 2x + 4
w = 9
A = 72

so we plug in what we know:

9(2x+4)=72

Then solve for x, and plug that value back into l = 2x + 4