Question

On a triangle, one side measures 4x2−2x and another side measures 2x2 −5x+1. If the perimeter of the triangle is 9x2 + x+6, what is the measure of the third side of the triangle? (Your answer will be an expression)

Answer 1

3x² + 8x + 5

Explanation:

Subtract the sum of the 2 given sides from the perimeter, that is

9x² + x + 6 - (4x² - 2x + 2x² - 5x + 1)

= 9x² + x + 6 - (6x² - 7x + 1 ) ← distribute parenthesis by - 1

= 9x² + x + 6 - 6x² + 7x - 1 ← collect like terms

= 9x² + 8x + 5