Atriangle has side lengths of 8 cm, 9 cm, and 14 cm. classify it as acute, obtuse, or right.

The correct answer is:

It is an obtuse triangle.

Explanation:

We use the Pythagorean Theorem to determine what type of triangle we have, based on the side lengths.

If a² + b² = c², the triangle is a right triangle.

If a² + b² < c², the triangle is an obtuse triangle.

If a² + b² > c², the triangle is an acute triangle.

Using 8 for a, 9 for b and 14 for c, we have:

8² + 9² and 14²

8² + 9² = 64+81 = 145

14² = 196

145 < 196; therefore a² + b² < c², and the triangle is obtuse.

m∠5 + m∠3 = m∠1   is true.

m∠5 + m∠6 = 180 is true

m∠2 +m∠3 = m∠6   is true

m∠2 +m∠3 +m∠5 = 180   is true