Question

a triangle has angle measurements of 39°, 54°, and 87°. what kind of triangle is it?
equilateral
isosceles but not equilateral
scalene

Explanation:

Step1: Recall triangle definitions

• Equilateral triangle: all angles equal (\(60^{\circ}\)).
• Isosceles triangle: at least two angles equal.
• Scalene triangle: all angles different.

Step2: Check given angles

Given angles \(39^{\circ}\), \(54^{\circ}\), \(87^{\circ}\) are all different.

Answer:

scalene