Question

Which lines are parallel if mZ1+ m2 2 = 180? Justify your answer.

Answer 1

Answer is choice A) j || k by the Converse of the Same Side Interior Angles Theorem

Lines j and k are the upward slanted lines on the left and right respectively. The transversal we only care about is line k. Line g is extra info put in there most likely to throw you off.

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The Same Side Interior Angles Theorem says that if two lines are parallel, then the same side interior angles (formed by the transversal cut) are supplementary. Those two same side interior angles add to 180 degrees. The converse reverses the direction of the theorem.

The converse says that if we know the same side interior angles are supplementary, then it leads to the two parallel looking lines to actually being parallel. So this is one way to check parallel-ness of two lines.

Answer 2

Answer:

Answer is choice A) j || k by the Converse of the Same Side Interior Angles Theorem

Explanation: