Answer:
x = 10, y = 15
Explanation:
(8x - 10) and 7x are alternate angles and congruent, thus
8x - 10 = 7x ( subtract 7x from both sides )
x - 10 = 0 ( add 10 to both sides )
x = 10
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Then 7x = 7 × 10 = 70
(6y + 20) and 7x are adjacent angles and supplementary, thus
6y + 20 + 70 = 180 , that is
6y + 90 = 180 ( subtract 90 from both sides )
6y = 90 ( divide both sides by 6 )
y = 15