Difference between revisions of "Complementary angles"

(Algebra)
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Two angles that add up to 90 degrees
 
Two angles that add up to 90 degrees
  
==Algebra==
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==Properties and Examples==
If <math>\angle A</math> is supplementary to <math>\angle B</math>, <math>\angle A + \angle B = 180</math> <math>degrees</math>
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===Property===
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<math>\angle A</math> is complementary to <math>\angle B</math> if and only if <math>\angle A + \angle B = 180</math> <math>degrees</math>
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===Examples===
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If <math>\angle A</math> is <math>29</math> <math>degrees</math> and <math>\angle B</math> is <math>61</math> <math>degrees</math>, angle A and angle B are complementary since <math>29 + 61 = 90</math>
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If <math>\angle A</math> is <math>30</math> <math>degrees</math> and <math>\angle B</math> is <math>62</math> <math>degrees</math>, angle A and angle B are not complementary since <math>30 + 62 = 92</math>, and not <math>90</math> degrees.
  
 
==Related Topics==
 
==Related Topics==

Revision as of 21:06, 3 January 2020

Diagram

[asy] import olympiad; size(150); pair D = (0, 10), C = (10, 5), B = (10, 0), A = (0, 0); draw(A--B); draw(C--A); draw(D--A); label("$A$", A, SW); label("$B$", B, SE); label("$C$", C, W); label("$D$", D, NE); [/asy]

As long as $\angle BAD$ is a right angle, $\angle BAC$ and $\angle CAD$ are complementary angles to each other.

Definition

Bing/Google

Either of two angles whose sum is 90°

Merriam-Webster

Two angles that add up to 90 degrees

Properties and Examples

Property

$\angle A$ is complementary to $\angle B$ if and only if $\angle A + \angle B = 180$ $degrees$

Examples

If $\angle A$ is $29$ $degrees$ and $\angle B$ is $61$ $degrees$, angle A and angle B are complementary since $29 + 61 = 90$

If $\angle A$ is $30$ $degrees$ and $\angle B$ is $62$ $degrees$, angle A and angle B are not complementary since $30 + 62 = 92$, and not $90$ degrees.

Related Topics

Supplementary

Right angles