Two parallel lines cut by a transversal are shown. What is the measure of X"?
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9514 1404 393
Answer:
x = 10
Step-by-step explanation:
The marked angles are "alternate interior" angles, so are congruent.
(x° +20°) = (4x° -10°)
30 = 3x . . . . . . . . . . . . . . . divide by °, add 10-x
10 = x . . . . . . divide by 3