Supplementary angles add to be 180 degrees. If one angle is 20. The supplement angle is 160.
180 - 20 = 160
160 is your answer.
I believe the answer is B: 3 + 7 + (-10).
Answer:
- c = -4.5
- z = 20
- x = -12
- a = -4/7
Step-by-step explanation:
A way to do this that will always work is ...
- eliminate parenthses and collect terms
- subtract any constants from the left side
- subtract any variable terms from the right side
- divide by the coefficient of the variable
1.
- 8c -11 -6c = -2
- 2c -11 = -2
- 2c = 9
- c = 4.5
2.
- 3z +4 -2z -9 = 15
- z -5 = 15
- z = 20
3.
- 12 -4x +18 = 36 +4x +18 -6x
- 30 -4x = 54 -2x
- -4x = 24 -2x
- -2x = 24
- x = -12
4.
- 36a -9a -5 = 6a -17
- 27a -5 = 6a -17
- 27a = 6a -12
- 21a = -12
- a = -12/21 = -4/7
all shapes with 4 angles are 360 degrees
100+96= 196
360-196= 164
c+d=164
80+84=164
D is 84
C is 80
