From the question, we were given:
The perimeter as 40 inches,
The length of the rectangle as 12 inches
We are asked to find the equation that can be used to find the width if it is represented by x.
recall that the formula for the perimeter of a rectangle is:
Perimeter (P) = 2(Length + Width)
P = 2(L + W)
Since we were told in the question that the width of the rectangle is = x
So let's input into the formula:
40 = 2(12 + x)
Therefore, the equation that can be used to find the width of the rectangle is:
40 =2(12 + x)