Respuesta :

Answer:

x = 20

Step-by-step explanation:

For the lines to be parallel, the angles have to be equal

2x+15 = 55

Subtract 15 from each side

2x+15-15 = 55-15

2x = 40

2x/2 = 40/2

x = 20

These are alternate interior angles which equal each other. The value that makes the two equal is 20. Since one angle equals 55 we should get another to be equal to 55. 2(20)+15=55. 55=55. The answer is a.20.