Complementary Angles Calculator
Find the angle that adds to your angle to make 90 degrees.
Formula
β = 90° − α
Complement β ≈ 90-(35)
How to use
- Enter an angle from 0° to 90°.
- Read its complement.
- Check that the two angles sum to 90°.
Examples
- 35° and 55° add to 90°.
Frequently asked questions
What are complementary angles?
Two angles whose measures add to 90°.
Must they be adjacent?
No. Their sum matters, not their location.
Are 0° and 90° accepted?
Yes, as boundary cases; an angle above 90° has no nonnegative complement.
Sources
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