Where is it? In order to help you I need to see what the problem is.
1. 3x+9-9=18-9
3x=9
x=3
2. 4x-12=20
4x-12+12=20+12
4x=32
x=8
3. x+0-0
x=0
4. x/2-2+2=9+2
x/2=11
(2)(x/2)=11(2)
x=22
5. 12x-21=3
12x-21+21=3+21
12x=24
x=2
6. 3x-15=18
3x-15+15=18+15
3x=33
x=11
7. 3x-25=14
3x-25+25=14+25
x=13
8. 3x+16=22
3x+16-16=22-16
x=2
9. 2x-8=2
2x-8+8=2+8
2x=10
x=5
10. 9x-18=9
9x-18+18=9+18
9x=27
x=3
11. x+0=0
x=0
12. 9x-8=19
9x-8+8=19+8
9x=27
x=3
If you want to check my answers
use substitution method by using the x into for each equation.
X= 0 (multiplicity of 1)
X= -2 (multiplicity of 1)
X= 2 (multiplicity of 2)
Answer:
A linear pair of angles is formed when two lines intersect. Two angles are said to be linear if they are adjacent angles formed by two intersecting lines. The measure of a straight angle is 180 degrees, so a linear pair of angles must add up to 180 degrees.