9514 1404 393
Answer:
- a) 2 and 4; b) 1&2, 2&3, 3&4
- x = 16
Step-by-step explanation:
1a. Vertical angles share a vertex and are composed of opposite rays. Here, angles 2 and 4 are vertical angles.
1b. Consecutively numbered angles are adjacent, as are angles 1 and 5. The pairs of interest can be chosen from ...
1&2, 2&3, 3&4, 4&5, 5&1
__
2. Angles 1 and 3 have the same measure, because they are vertical angles. Then we have ...
78° = (5x -2)°
80 = 5x . . . . . . . divide by °, add 2
16 = x . . . . . . . divide by 5
