An angle measures such that its supplementary angle is four times its complementary angle. What is the measure of this angle in degrees?
Answer and explanation
Correct answer: B. 60 degrees
- Step 1: Let the angle be x. Supplementary angle is 180 - x; complementary angle is 90 - x. Step 2. Set up equation: 180 - x = 4(90 - x) => 180 - x = 360 - 4x => 3x = 180 => x = 60 degrees. Answer: 60 degrees. Why not the others: 30 degrees gives supplement 150 and complement 60 (ratio 2.5); 45 degrees gives 135 and 45 (ratio 3); 75 gives 105 and 15 (ratio 7).
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