Answer:

Step-by-step explanation:
Since we have two parallel lines, therefore the measure of angle B is a right angle [90°]. Then you automatically would see that the measure of angle C is 70°, according to the Vertical Angles Theorem. Then you use the Triangular Interior Angles Theorem to find the

180° = 70° + 90° + m∠A
180° = 160° + m∠A
- 160° - 160°
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The m∠A is 20°, therefore the m∠x is also 20°, according to the Vertical Angles Theorem.
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