Perimeter of the triangle = 6p2 – 4p + 9
Two sides are;
Side one = p2 – 2p + 1 and
Side two = 3p2 – 5p + 3
Let’s take third side be = x
As we know perimeter of a triangle = sum of all the sides
So, we have
6p2 – 4p + 9 = {(p2 – 2p + 1) + (3p2 – 5p + 3) + (x)}
6p2 – 4p + 9 = p2 – 2p + 1 + 3p2 – 5p + 3 + x
6p2 – 4p + 9 - p2 + 2p – 1 - 3p2 + 5p - 3 = x
Let’s make the pairs;
(6p2 – p2 – 3p2) + (- 4p + 2p + 5p) + (9 – 1 – 3) = x
2p2 + 3p + 5 = x
The required side is 2p2 + 3p + 5.