first side = x
second side = x - 3
third side = 2x
The perimeter = 49 cm and is equal x + (x - 3) + 2x
The equation:
x + x - 3 + 2x = 49
(x + x + 2x) - 3 = 49
4x - 3 = 49 |+3
4x = 52 |:4
x = 13 cm
x - 3 = 13 - 3 = 10 cm
2x = 2(13) = 26 cm
Answer: 13cm, 10cm, 26cm.