algebragal algebragal 13-10-2020 Mathematics contestada 5. A triangle has side lengths 3x2 + 5x –1, 6x2 + 5, -7x +1. Which of the following expressions represents the perimeter of the triangle? A. 9x2 + 2x + 5 B. 9x2 – 2x + 5 c. 9x2 + 2x + 4-1 D. 9x2 – 5x + 7x + 5