Question

A triangle has a perimeter of 81 inches. The side lengths can be found by x, 3x-1, and 4x+2
what is the value of x?

Answer 1

81 = x + 3x - 1 + 4x + 2

81 = 8x + 1

80 = 8x

10 = x

Answer 2

x + 3x-1 + 4x +2 = 81
8x+ 1 = 81
8x+1-1 = 81-1
8x = 80
8x/8 = 80/8

x = 10

Answer 3

10