Answer:
20. 44
21. 9
22. 94
23. 116
24. 17
25. 13
Explanation:
Keep in mind complementary and supplementary angles. When two angles are right next to each other on a straight line, they add up to 180 degrees, such as the angles in 22 and 23. The other two angles are complementary angles since they add up to 90 degrees. So to solve for b, subtract the angle you are given from either 90 or 180 depending on if it is complementary or supplementary.
For question 20:
90 = b + 46
90 - 46 = b
b = 44
Then do the same for 21.
For question 22:
180 = b + 86
180 - 86 = b
b = 94
Then do the same for 23.
For the last two questions you need to remember that angles that are diagonal from each other are equivalent angles, so they equal each other.
For question 24:
70 = 4x+2
68 = 4x
x = 17
Do the same for 25.
83 = 6x+5
78 = 6x
x =13