A figure with parallel lines m and n is shown below. What is the measure of angle b?
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Answer:
42°
Step-by-step explanation:
[tex]\therefore b + 48 \degree + 90 \degree = 180 \degree \\ b + 138 \degree = 180 \degree\\ b = 180 \degree - 138 \degree \\ b = 42 \degree [/tex]