Question

Perimeter of triangle. I don't understand what I did wrong, please help

Answer 1

This is an isosceles triangle, so 3x-5 = 19-x.  Thus, 4x=24, and x=6.

Thus, the 3 sides of the triange are 3(6)-5, 19-6 and 2(6), or 13, 13 and 12.

The perimeter is the sum of these three side lengths:  13+13+12 = 38 (ans.)