Answer:
x = 9
Step-by-step explanation:
2 sides are 4 less than x, that is x - 4
The perimeter is the sum of all 3 sides, thus
x + x - 4 + x - 4 = 19, that is
3x - 8 = 19 ( add 8 to both sides )
3x = 27 ( divide both sides by 3 )
