An acute angle (angle less than 90 degrees).
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The complement of an acute angle A is the angle 90 degrees. So for a 50 degree
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an angle's complement is 90 degrees  the given angle for example  lets say the given angle is 50 degrees it's complement would be 90  50 = 40 degrees
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Two Angles are Complementary if they add up to 90 degrees. therefore, 9040=50. the angle is 50 degrees.
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