1. What Are Complementary Angles?

Two angles are complementary when their measures add up to 90 degrees (a right angle). If one angle is known, its complement can be found by subtracting from 90°.

2. How the Calculator Works

The calculator uses the complementary angles formula:

Where:

• Known Angle — Must be between 0° and 90°
• Complementary Angle — Result will also be between 0° and 90°

3. Practical Applications

Geometry: Complementary angles are fundamental in right triangle trigonometry and many geometric proofs.

Construction: Used when creating perpendicular structures or calculating support angles.

4. Using the Calculator

Instructions: Enter any angle between 0° and 90° to find its complement. The calculator will show the angle that completes it to 90°.

5. Frequently Asked Questions (FAQ)

Q1: Can an angle have more than one complement?
A: No, each angle between 0° and 90° has exactly one unique complement.

Q2: What if I enter 90 degrees?
A: The complement would be 0°. An angle of 90° is its own complement.

Q3: Are the angles in a right triangle complementary?
A: The two non-right angles in a right triangle are always complementary.

Q4: How is this different from supplementary angles?
A: Supplementary angles add to 180° (a straight line), while complementary angles add to 90°.

Q5: Can complementary angles be negative?
A: No, angle measures are always positive in this context.