Answer:
x = 10
Square perimeter = 84cm
Triangle perimeter = 84cm
Explanation:
Hello!
First, we make an equation to find the perimeter of each shape
For a square we multiple one side by 4
(2x + 1) * 4
Simplify
8x + 4
An equilateral triangle means each side is equal so we can multiply one side by 3
(3x - 2) * 3
Simplify
9x - 6
The problem states they are equal to each other so we can show that
8x + 4 = 9x - 6
Now we can solve for x
Subtract 8x from both sides
4 = x - 6
Add 6 to both sides
10 = x
Now we can put x into our original equations for the perimeters
Square
8(10) + 4
80 + 4
84cm
Triangle
9(10) - 6
90 - 6
84cm
Hope this Helps!