Okay so, vertical angles have the same measure. So, using that logic, <1 and <4 have the same measure of 71.
<4 is an alternate interior angle to <5. We know that alternate interior angels have the same measure. So < 5 is also 71.
Since <5 and <7 are supplementary angles, that tells us that their angles added together should add up to 180.
180 - 71 = 109
I believe the answer should be 108
