13) The perimeter of a triangle is 69 cm. The first side is 5 cm shorter than the second side. The third side is twice as long as the first side. Find the length of each side.

Answer 1

x = y-5, z = 2x, x+y+z = 69

y-5 + y + 2(y-5) = 69

4y = 69 +5 +10 = 84

y = 21

x = 21-5 = 16

z =2(16) = 32

sides are 16, 21 and 32 cm