I believe the next one would be 13.2 because if you add 8.4 to -6.4 it gets 4.8 so you just do the same thing
Answer:
2x+20 + x+40 = 180
Step-by-step explanation:
The angles are supplementary so they add to 180
2x+20 + x+40 = 180
It is a part of slope form ( intercept
What do you want us to answer??