Answer:
The perimeter of triangular sign is 12x+3
Explanation:
Length of side1 of triangle = x inches
Length of side2 of triangle = 4x-5 inches
Length of side3 of triangle = 7x+8 inches
We need to find perimeter of triangular sign.
The formula used is:

Now, finding perimeter of triangular sign:

The perimeter of triangular sign is 12x+3