One side of a square measures x + 3 inches. One side of an equilateral triangle measures x + 7 inches. If the perimeters of the two figures are equal, what is the value of x?

The answer to your question is x = 9

Step-by-step explanation:

Data

Side of a square = s = x + 3

Side of a triangle = s = x + 7

Perimeter of a square = 4s

Perimeter of a triangle = 3s

Process

1.- Consider both perimeters are equal

                    Perimeter of a square = Perimeter of a triangle

2- Substitution

                             4(x + 3) = 3(x + 7)

3.- Expand

                            4x + 12 = 3x + 21

4.- Solve for x

                             4x - 3x = 21 - 12

                                      x = 9

-2x + 7 = 7

subtract 7 from both sides.

-2x = 0

divide both sides by -2.

x = 0