Question

what is the perimeter of the triangle shown?

Explanation:

Step1: Recall perimeter formula

Perimeter of triangle = sum of sides

Step2: Add the side - lengths

$(5r^{2}+3)+(4r^{2}-8r + 1)+(7r - 8)$

Step3: Combine like - terms

$(5r^{2}+4r^{2})+(-8r + 7r)+(3 + 1-8)$

Step4: Simplify

$9r^{2}-r - 4$

Answer:

$9r^{2}-r - 4$