Vertical angles, because the definition of vertical lines is each of the pairs of opposite angles made by two intersecting lines.
Answer:
Step-by-step explanation:
<span>1 times 2 times 3 times 4 times 5 = 120 </span>
18. -4, 4
19. -38, 38
20. -260, 260
21. -4092, 4092.
I might be wrong but...