Question

The longest side of a triangle is two times the shortest side. The medium side is 3 meters more than the shortest side. Perimeter is 27 meters. Find the dimensions

Answer 1

let the longest side=x
medium side=y
shortest side=z

x=2z
y=z+3
x+y+z=27

now solve

Answer 2

Let x, y and z be the longest, medium and shortest sides respectively:
x = 2z
y = z+3
z = z

x+y+z = 27, so
(2z)+(z+3)+(z) = 27,
4z+3 = 27,
z = 8

The rest should follow.