Answer:
14x + 23
Step-by-step explanation:
The lengths of three sides of a triangle are 5x + 9 feet, 2x + 14 feet, and 7x feet.
The perimeter of a triangle: the sum of all of its sides.
5x + 9 + 2x + 14 + 7x
14x + 23
It's the expression of the perimeter of the triangle. Once you will be asked to find x, you'll probably be given the exact perimeter of the triangle.