2 equal sides of a triangle are 4m less than 3 times the third side find the sides of the triangle if the perimeter is 55cm.

Let x be the length of the equal sides and y be the third side.

2x + y = 55 from the perimeter rule
x = 3y - 4 from the relative lengths
2x -6y = -8 previous eq
7y = 63
y = 9 cm
x = 3y -4 = 23 cm