Question

If a triangle has sides x +3, 2x +5 and the perimeter is 7x, what is the expression for the missing side

Answer 1

4x -8

Explanation:

The perimeter is the sum of the side lengths:

P = a + b + c

7x = (x +3) +(2x +5) +c . . . . fill in the given information

7x = 3x +8 + c . . . . simplify

4x -8 = c . . . . . . . . . subtract (3x+8) from both sides

The missing side is 4x-8.