Understanding Complementary and Supplementary Angles
Key Concepts
1. **Complementary Angles**: Two angles that add up to 90 degrees.
2. **Supplementary Angles**: Two angles that add up to 180 degrees.
Detailed Explanation
Complementary Angles
Complementary angles are two angles whose measures sum to exactly 90 degrees. If the two angles are adjacent (sharing a common vertex and side), they form a right angle. For example, if one angle is 30 degrees, its complementary angle is 60 degrees because \(30 + 60 = 90\).
Supplementary Angles
Supplementary angles are two angles whose measures sum to exactly 180 degrees. If the two angles are adjacent (sharing a common vertex and side), they form a straight line. For example, if one angle is 120 degrees, its supplementary angle is 60 degrees because \(120 + 60 = 180\).
Examples
Example 1: Find the complementary angle of 45 degrees.
Solution: Since complementary angles add up to 90 degrees, the complementary angle is \(90 - 45 = 45\) degrees.
Explanation: Both angles are 45 degrees, forming a right angle.
Example 2: Find the supplementary angle of 135 degrees.
Solution: Since supplementary angles add up to 180 degrees, the supplementary angle is \(180 - 135 = 45\) degrees.
Explanation: The two angles together form a straight line.
Analogies
Think of complementary angles as two pieces of a puzzle that fit together to form a right angle, like the two sides of a right triangle. Supplementary angles, on the other hand, are like two pieces of a straight line that fit together to form a straight path, like the two halves of a straight road.
Practical Application
Understanding complementary and supplementary angles is essential in various real-world scenarios, such as in architecture, design, and navigation. By mastering these concepts, you can better analyze and solve problems involving angles and shapes in everyday life.