What is the measure of ∠4?
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Answer:
80 degrees
Step-by-step explanation:
angle 1 is equal to 100 because of the law of exterior angles. And since andgle 1 and 2 make 180 degrees we can subtract 80 from 100 and we get the measure of angle 2. Angle 2 and 4 are the same becasue of the law of adjacent angles.