Question

find the measure of an angle which is 40° less than its complement

Answer 1

The sum of angles that are complementary is always 90 degrees. Say x is one of the angles. The other is 40 less than x, so x - 40. 

angle 1 +angle 2 = 90 
x + x - 40 = 90 
Add 40 to each side. 
x +x = 130 
2x = 130 
Divide by 2. 
x = 65 

One of the angles is 65 degrees, and the other is 40 degrees less, meaning its 25 degrees.

Answer 2

180-40=140

140 will be its complement and 40 less is equal to 100 degree

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