First identify the angle RELATIONSHIP, then find the measure of the angle indicated in bold.
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Answer:
Same-side interior angles
m∠ = 80°
Step-by-step explanation:
Step 1: Set up equation
x + 85 + x + 105 = 180
Step 2: Combine like terms
2x + 190 = 180
Step 3: Isolate x and solve
2x = -10
x = -5
-5 + 85 = 80°