Question

Help?

Answer 1

The perimeter is the distance around the triangle.
They give you 14x^2 - 3x +15 as the perimeter.
They give you the distance of two sides so to find the third side, just subtract the two sides they give you from the perimeter.
An easy way would be to add the two sides together and just subtract that total from the perimeter.

(14x^2 - 3x + 15) - [(4x^2 - x + 8) + (9x^2 + 3x - 2)]

Just combine like terms.

(14x^2 - 3x + 15) - (13x^2 + 2x + 6)

14x^2 - 13x^2 = x^2
-3x - 2x = -5x
15 - 6 = 9

The last side would be x^2 - 5x + 9

Tell me if you need anything explained! :)

Answer 2

Thank you so much!