Question

Write an equation that represents the perimeter of triangle. Combine like terms.

Answer 1

The perimeter of a figure is the sum of all the side lengths. This triangle has the side lengths 3x, 3x, and 15.

Perimeter = 3x + 3x + 15

Perimeter = 6x + 15

Now, if we are given the numerical value of the perimeter, then we can plug that in and solve for x.

90 = 6x + 15

6x = 75

x = 12.5

Hope this helps!