GED Math Practice Test

What best describes a right triangle?

1. A triangle with one right angle

2. A triangle with equal sides

3. A triangle with all acute angles

4. A triangle with all right angles

The correct answer is: A triangle with one right angle

A right triangle is best described as a triangle with one right angle, which is an angle that measures exactly 90 degrees. This specific characteristic is what differentiates right triangles from other types of triangles. In contrast, a triangle with equal sides describes an equilateral triangle, where all three sides and angles are the same. A triangle with all acute angles refers to an acute triangle, where every angle is less than 90 degrees. Lastly, a triangle with all right angles would not exist in Euclidean geometry, as the angles in a triangle must sum to 180 degrees, making it impossible for all angles to be 90 degrees. Therefore, the definition of a right triangle being one that contains exactly one right angle is the correct and precise choice.