Question

the width of a rectangle is 3x+1. the length is three times the width. what is the simplified expression of the total perimeter of this rectangle?

Answer 1

The total perimeter here is P =21x + 7

Explanation:

Let W and L represent the width and length of the rectangle. Then the perimeter is P = 2W + 2L. Substituting 3x + 1 for W and 3(3x + 1) for L, we get

P = 2(3x + 1) + 2*3*(3x + 1), or P = 7(3x + 1) = P =21x + 7