Answer:
40 feet
Step-by-step explanation:
The perimeter of a triangle is the distance around the triangle. It can be found by adding all the sides together. First, find the amount each side is by substituting x = 4 and simplifying.
3x - 4 = 3(4) - 4 = 12 - 4 = 8
x² -1 = (4)² - 1 = 16 - 1 = 15
2x² - 15 = 2(4)² - 15 = 32 - 15 = 17
Add the sides together, 8 + 15 + 17 = 40 feet
