Respuesta :

make them = to one another
(3x+12)°=48° because they are alternate exterior angles of // lines
subtract 12 from both sides
3x=36
divide 3 from both sides
x=12
your answer is B

The value of the x is 12.

The correct answer is an option (B)

What are parallel lines?

"Lines in the same plane that are at equal distance from each other and never meet."

What  is transversal?

"A line that intersects two or more other lines."

For given question,

Line m and line n are parallel lines.

Also angle (3x + 12) and angle 48 degrees are alternate exterior angles.

We know that, alternate exterior angles are congruent.

⇒ 3x + 12 = 48

⇒ 3x = 48 - 12

⇒ 3x = 36

⇒ x = 12

Therefore, the value of the x is 12.

The correct answer is an option (B)

Learn more about  alternate exterior angles here:

https://brainly.com/question/2279752

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