Question

Find the measure of ∠1. Justify your answer.

A.
m∠1 = 60 because corresponding angles of parallel lines are supplementary.


B.
m∠1 = 120 because corresponding angles of parallel lines are congruent.


C.
m∠1 = 120 because same-side interior angles of parallel lines are congruent.


D.
m∠1 = 60 because same-side interior angles of parallel lines are supplementary.

Answer 1

B

Explanation:

line a and line b are parallel

angle 1 is corresponding to 120

in 2 parallel lines the coressponding angles are equal

so angle 1 = 120

Answer 2

The correct answer option is: B. m∠1 = 120 because corresponding angles of parallel lines are congruent.

Explanation:

We are given a diagram where two parallel lines are intersected by a transversal.

We know that, if two parallel lines are cut by a transversal, then the alternate interior angles formed are congruent.

So here, the angle numbered 1 and the angle measuring 120° are congruent.

Therefore, m∠1 = 120° so option B is correct.