2020 · Q78
In a triangle ABC, if 2∠A = 3∠B = 6∠C, then what is ∠A + ∠C equal to?
Elementary MathematicsGeometry: Lines, Angles and Triangles
- A90°
- B120°
- C135°
- D150°
Explanation
2A = 3B = 6C = 6k gives A = 3k, B = 2k, C = k; 6k = 180 so k = 30. A+C = 4k = 120 degrees - option (B). Check: 90+60+30 = 180 degrees - a valid triangle.