how do you find the measure of angle b with only angle c and the outside of angle a
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Step-by-step explanation:
straight angle a + 117 = 180
a = 180 - 117
= 63
total angle in triangle = 180
63 + b + 81 = 180
b = 180 - 63 - 81
= 36
Answer:
b = 36°
Step-by-step explanation:
the exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.
117° is an exterior angle of the triangle , then
b + 81° = 117° ( subtract 81° from both sides )
b = 36°