3.6. Same Side Interior Angles http://www.ck12.org
James Sousa: Proof of Consecutive Interior Angles Converse
Guidance
Same Side Interior Anglesare two angles that are on the same side of the transversal and on the interior of the two
lines.^63 and^65 are same side interior angles.
Same Side Interior Angles Theorem: If two parallel lines are cut by a transversal, then the same side interior
angles are supplementary.
So, ifl||mand both are cut byt, thenm^63 +m^65 = 180 ◦andm^64 +m^66 = 180 ◦.
Converse of the Same Side Interior Angles Theorem:If two lines are cut by a transversal and the consecutive
interior angles are supplementary, then the lines are parallel.
Example A
Using the picture above, list all the pairs of same side interior angles.
Same Side Interior Angles:^6 4 and^6 6,^6 5 and^6 3.