Answer:
B. 9
Step-by-step explanation:
We know that a full circle should equal 360°, that'll help!
Since the 140°+3x+13 should equal to 180, because that makes the half of the circle it covers, we know how to set up our equation!
It should look like this:
3x+13=40
ISOLATE YOUR VARIABLE:
- Subtract 13 from both sides
NEXT, CONTINUE ISOLATING:
3x=27
- Divide by 3 from both sides.
FINALLY:
You will get X=9!
