A triangle has 2 angles that each measure 81°. What kind of triangle is it?

2 Answers
Mar 3, 2018

Isosceles

Explanation:

Hey!

If this triangle as two of the same angles, then we know there are two correlating sides of equal length. As such, the triangle must be isosceles!

If there were three similar angles (#45°#), then the triangle would be equilateral.

If there were no matching angles, then the angle would be scalene, as there would be no equal side lengths.

Good luck!

Mar 3, 2018

Isosceles triangle
Also an acute triangle

Explanation:

An isosceles triangle is a triangle in which two of the three sides are the same length, or two of the three angles are the same degree.

An acute triangle is a triangle in which all of its angles are acute angles (less than 90°). If two of the three angles are 81°, the remaining angle is #180°-81°-81°=18°#, which are all less than 90°.