complementary angle
Adds to ninety
Complementary angles are two angles that together add up to 90 degrees—a right angle.
If one angle measures 30 degrees, its complement is 60 degrees.
The term appears most often in geometry: Find the complementary angle to 45 degrees.
Not to be confused with supplementary angles, which sum to 180 degrees.
Opposite over hypotenuse
- cosineRatio in triangle math
- cofunctionTrigonometric complement pair
- tangentLine touching curve once
- cotangentTangent reciprocal function
secant · cosecant · identity · ratio · hypotenuse · opposite · unit circle · trigonometric functions
Angle-measuring instrument
- degreesUnits of measurement
- arcminute1/60th of a degree
- arcsecondMinute angular unit
- 90 degreesMeasure of perpendicularity
sum · calculation · subtraction · radian · quadrant · rotation · measurement · precision
Serving to complete
- adjacentDirectly next to
- acuteIntensely severe or perceptive
- obtuseLacking mental sharpness
- congruentIdentical in form
transversal · parallel · perpendicular · bisect · vertex · protractor · degrees · theorem
sine
Opposite over hypotenuse
- cosineRatio in triangle math
- cofunctionTrigonometric complement pair
- tangentLine touching curve once
cotangent · secant · cosecant · identity · ratio · hypotenuse · opposite · unit circle · trigonometric functions
protractor
Angle-measuring instrument
90 degrees · sum · calculation · subtraction · radian · quadrant · rotation · measurement · precision · calibration
supplementary
Serving to complete
congruent · transversal · parallel · perpendicular · bisect · vertex · protractor · degrees · theorem
complement, complementary, complemented, complementing, complements, angle, angles, angled, angling