Question

a triangle has side lengths of $(7x - 4)$ centimeters, $(x + 3)$ centimeters, and $(3y + 2)$ centimeters. which expression represents the perimeter, in centimeters, of the triangle?
answer
$1 + 3y + 8x$
$5y + 7x$
$3x + 5y + 4$
$-1 + 5y + 8x$

Explanation:

Step1: Sum all side lengths

$(7x - 4) + (x + 3) + (3y + 2)$

Step2: Group like terms

$(7x + x) + 3y + (-4 + 3 + 2)$

Step3: Simplify each group

$8x + 3y + 1$

Answer:

$1 + 3y + 8x$