SOLUTION
A
1-2: Given 2°
Complement
Supplement
3-4: Given 15°
Complement
5-6: Given 57.5°
Complement
- 90-57.5 = 32.5°
- 180-57.5 = 122.5°
B
7-8: Given 25° and 90°
- Complement of 25° is 65°
- 90-25 = 65°
9-10: Given 2x and 100
- 2x+100=180
- 2x=180-100
- 2x=80
- x=40
11-12: Given 4x+30 and x+15
- 4x+30 + x+15 = 180
- 5x+45=180
- 5x=180-45
- 5x=135
- x=135÷5
- x=27
13-14: Given 45° and 3x+9
Opposite angles are equal
- 45 = 3x+9
- 45-9 = 3x
- 36=3x
- 36÷3=x
- 12=x
C
15-16:
Opposite angles are equal. If two angles are on thesame line , then they have a sum of 180°.
Finding for the angle 2:
- They are opposite angles are equal thus, If one is 98° , then angle 2 is 98°
Findin for the angle 1:
- 98 and angle 1 is on the same line thus, we will add them and equate to 180.
- 98 + <1 = 180
- <1 = 180 - 98
- <1 = 72°
17-18:
- Notice that , 121 and 3 are opposite angles , and 3 and 4 are opposite angles also. Hence they are all equal.
Finding for the angle 3:
Finding for the angle 4:
- <3 = <4
- 121° = 121°
- angle 4 is 121°
