Canadian Forces Aptitude Test (CFAT) Practice

Which of the following best describes a right triangle?

1. All sides are equal

2. One angle measures 90 degrees

3. It has two equal angles

4. It is a polygon with four sides

The correct answer is: One angle measures 90 degrees

A right triangle is defined specifically by having one of its angles measuring 90 degrees. This is a fundamental characteristic of right triangles, distinguishing them from other types of triangles. The presence of this right angle is crucial in many mathematical applications, particularly in trigonometry and geometry, where it allows for the use of various theorems and formulas, such as the Pythagorean theorem. The other options describe different geometric properties: having all sides equal pertains to an equilateral triangle; having two equal angles describes an isosceles triangle; and being a polygon with four sides refers to a quadrilateral. None of these options provide the correct definition of a right triangle, making the identification of a 90-degree angle the key factor.