Length of each side = 11 cm
Solution:
Let a be the side of the square.
Side length of square = Side length of equilateral triangle
Therefore, side length of equilateral triangle = a
Perimeter of the square = Number of sides × side
= 4 × a
Perimeter of the square = 4a
Perimeter of the equilateral triangle = Number of sides × side
= 3 × a
Perimeter of the equilateral triangle = 3a
Sum of the perimeter of a square and equilateral triangle = 77 cm
⇒ 4a + 3a = 77
⇒ 7a = 77
Divide by 7 on both sides of the equation, we get
⇒ a = 11 cm
Length of each side = 11 cm.
