Is an isosceles triangle an example of an acute angle?

For starters, here are the basic rules of triangles.

• A right angle is 90 degrees.
• An acute angle is less than 90 degrees.
• An obtuse angle is more than 90 degrees.
• A triangle's angles always add up to 180 degrees.
• An isosceles triangle has two sides that are the exact same length and thus two same angles.

Now, an isosceles triangle can have all acute angles. For example, its angles can measure in degrees at 80, 50, and 50. However, isosceles triangles can also have an obtuseangle.

For example, consider a triangle with the following angle degree measures: 96, 42, 42.

With the rules above in mind, the triangle above is an isosceles triangle because two angles are the same and they both are acute. At the same time, the remaining angle is greater than 90 degrees and so is obtuse. Thus, a single triangle can have both acute and obtuse angles.

Similarly, you can have a right triangle that is also isosceles, with the angle degree measurements at 90, 45, and 45.