Answer:
Option C is the correct answer.
Step-by-step explanation:
We have been given that a and b are parallel to each with a straight angle.
If a and a are parallel, then angle suspended by a and b will be equal to each other. It is because of Alternate angle of triangle.
Let's head to the question.
According to the above statement, we have the following equation.
2x°= 4x -30°
0r, 2x° - 4° = -30°
0r, -2x° = -30
0r, 2x° = 30°
0r, x = 30°/2°
0r, x = 15°
Hence, x = 15° will show that lines a and b are parallel.
