The lengths of sides of a triangle are (3x+2), (2x+5), and 4x. Terrel correctly added the lengths of the three sides to find the perimeter. What expression did Terrel write for perimeter?

(3x+2) + (2x+5) + 4x = 5x + 7 + 4x = 9x + 7

Teri wrote the expression 9x + 7 for perimeter.

So permiter=masure of all sides added together

so sides are (3x+2), (2x+5), and (4x)

so (3x+2) + (2x+5) + (4x)

use associative property

a + (b+c) = (a+b) + c so

(3x+2) + (2x+5) + (4x) = 3x+2+2x+5+4x

group like terms becasue can move numbers around

(3x+2x+4x) + (2+5)

add like terms

(9x) + (7)

9x+7

he will use 9x+7=perimiter