Which formula gives the perimeter of a triangle?

Which formula gives the perimeter of a triangle?

• A. P = a + b + c
• B. A = 1/2 bh
• C. A = s^2
• D. P = 2(a + b)

Answer: (A)

Perimeter is the total distance around a polygon, so for a triangle you add up the lengths of all three sides. That gives P = a + b + c, where a, b, and c are the side lengths. The other formulas describe area or apply to different shapes: area of a triangle is (1/2)bh, area of a square is s^2, and P = 2(a + b) is the perimeter of a rectangle with sides a and b. So the correct formula for a triangle’s perimeter is the sum of its three side lengths.

Perimeter is the total distance around a polygon, so for a triangle you add up the lengths of all three sides. That gives P = a + b + c, where a, b, and c are the side lengths. The other formulas describe area or apply to different shapes: area of a triangle is (1/2)bh, area of a square is s^2, and P = 2(a + b) is the perimeter of a rectangle with sides a and b. So the correct formula for a triangle’s perimeter is the sum of its three side lengths.