T h ose tw o an g l es m e a s u re 18 0 ∘ x − an g l e x + 89 = 180 ∣ s u b t r a c t 89 x = 9 1 ∘ Ot h er an g l e m e a s u res 9 1 ∘ .
A "straight angle" is a straight line. The angle of a straight line is 180 degrees. The value of 2 angles add together to make 180 One of the angles = 89 degrees The value of the second angle = 180-89 = 91
The other angle measures 91 degrees since a straight angle is 180 degrees and 180 - 89 = 91. Together, the two angles form a straight line. Thus, their measures add up to 180 degrees.
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