1) Answer: x = 9
<u>Step-by-step explanation:</u>
Same Side Interior Angles are supplementary
15 + 5x + 14x - 6 = 180
19x + 9 = 180
19x = 171
x = 9
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2) Answer: x = 9
<u>Step-by-step explanation:</u>
Corresponding Angles are congruent
13x - 7 = 11x + 11
2x = 18
x = 9
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3) Answer: x = -10
<u>Step-by-step explanation:</u>
Alternating Interior Angles are congruent
90 = x + 100
-10 = x
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3) Answer: x = 7
<u>Step-by-step explanation:</u>
Alternating Exterior Angles are congruent
17x + 1 = 120
17x = 119
x = 7