The expression for the perimeter of the triangle is 6x + 21.
The triangle in the mural has three sides.
Let's start by assigning variables to the sides of the triangle:
Let x = length of the bottom of the triangle
One side = 8 + 4x
Another side = x + 13
The perimeter of a triangle is the sum of the lengths of its sides. So, to find the perimeter, we add up the lengths of the three sides:
Perimeter = x + (8 + 4x) + (x + 13)
To simplify the expression, combine like terms:
Perimeter = 6x + 21
So, the simplified expression for the perimeter of the triangle is 6x + 21.