The shorter side of the triangle is 18 cm and each of the longer sides are 54 cm
Solution:
Given that triangle has perimeter of 126 cm
Let the length of the shorter side of the triangle be "a"
The 2 longer sides are 3 times as long as the shortest side
So length of 2 longer sides = 3(length of the shorter side)
length of 2 longer sides = 3a
The perimeter of triangle is given as:
perimeter of triangle = length of the shorter side + length of 2 longer sides
perimeter of triangle = a + 3a + 3a
126 = a + 3a + 3a
7a = 126
a = 18
So length of shorter side = 18 cm
length of 2 longer sides are each = 3a = 3(18) = 54 cm
Thus, the shorter side of the triangle is 18 cm and each of the longer sides is 54 cm