2025 · Q74
An angle is one-fourth of its complement. What is the angle?
Elementary MathematicsGeometry: Lines, Angles and Triangles
- A12°
- B15°
- C18°
- D22.5°
Explanation
If the angle is x, its complement is 90-x, so x = (90-x)/4. Then 5x = 90 and x = 18 degrees. Setting up 'complement' as 90-x correctly is the whole task.