Question

One side of an equilateral triangle is 7dm shorter than one side of a square. The sum of the perimeters of the two figures is 49dm. Find the perimeter of each figure.

Answer 1

Let the side length of the square = s
Then the side length of the triangle = s - 7
Perimeter of triangle = 3(s - 7)
Perimeter of square = 4s
Sum of perimeters = 49 = 3(s - 7) + 4s
49 = 3s -21 + 4s ...............(1)
Now you just need to solve equation (1) to find the value of s.