Question

A triangle has sides with lengths of 13 kilometers, 18 kilometers, and 20 kilometers. Is it a right triangle?

Answer 1

No, it is not a right triangle

Explanation:

Lets explain how to check the sides lengths which formed a right angled triangle

In triangle ABC :

• If AC is the longest side in length

• If (AC)² = (AB)² + (BC)²

• Then, AB , BC , AC formed a right angle triangle in ∠B (opposite to AC) is a right angle and AC is the hypotenuse

The lengths of the sides of the triangle are 13 km, 18 km, 20 km

∵ The length of the longest sides is 20 km

- Find its square

∵ (20)² = 400

∴ The square of the length of the longest side is 400

∵ The length of the shortest sides are 13 km and 18 km

- Find the sum of their squares

∵ (13)² + (18)² = 169 + 324 = 493

∴ The sum of the squares of the lengths of the shortest sides is 493

∵ 400 ≠ 493

∴ The sides of 13 km, 18 km and 20 km CAN NOT be sides of

a right triangle

No, it is not a right triangle