Answer: x = 10
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Work Shown:
Corresponding angles are congruent when we have parallel lines.
5x-10 = 2x+20
5x-2x = 20+10
3x = 30
x = 30/3
x = 10
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5x-10 = 5*10-10 = 50-10 = 40
2x+20 = 2*10+20 = 20+20 = 40
Each angle is 40 degrees, which helps confirm our answer.