Question

The perimeter of a triangle is 6p + 2q - 5 units. One side length is p - 3 units. The second side length is 2p + 3q units. Which expression represents the length, in units, of the third side of the triangle?

Answer 1

Answer: 3p-q-2

Explanation:

Perimeter is the sum of all the sides.

Add the known sides together:

(p-3) + (2p+3q) = 3p + 3q - 3

To find the unknown side, subtract the sum of the 2 known sides from the perimeter (combine like terms):

(6p+2q-5) - (3p+3q-3) = 3p-q-2

Add all 3 sides together as a check of your answer!