Answer:
Explanation:
The two angles marked with expressions in x are alternate interior angles, so are congruent.
3x -4 = 5x -38
34 = 2x . . . . . . . . add 38-3x
17 = x . . . . . . . . . . divide by 2
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The two marked angles interior to the right triangle are complementary.
(7y -20) +(5·17 -38) = 90
7y = 63 . . . . . . . . . . . . . . . subtract 27
y = 9 . . . . . . . . . . . . . . . . . divide by 7