Y=21
Step-by-step explanation:
Given: lines l and m are parallel, and line t is a transversal.
angle pair result/justification
1 and 2 are equal (vertical angles)
6 and 8 are equal (corresponding angles)
1 and 4 are equal (alternate exterior angles)
4 and 8 are supplementary angles (i.e. add up to 180 degrees, a straight angle)
Note:
alternate angles are on opposite sides of the transversal, and each attached to a different (parallel) line.
If they are both enclosed by the parallel lines, they are alternate interior angles (examples: angles 2 and 3, 6 and 7)
If they are both outside of the two parallel lines, they are alternate exterior angles (examples: angles 1 and 4, 5 and 8)
H. 66
One triangle equals 180 degrees so you subtract 48 - 180= 132. Then you divide 132 by two because the bottom two angles are equal so 132/2 equals 66
Sorry that was confusing hope this helps!
