Answer:
x=21/4
Step-by-step explanation:
1. combine like terms
-4+-7= -11 3x-2x=x
2. subtract x
5x-11=x+10
4x-11=10
3. add 11
4x=21
4. divide 21 by 4 = 21/4
6 and a 4 on the top beside it
Basically, this is saying that 80% of (x) = 2 so you have know what the whole would be. It would be 2.5 because 80% of 2.5 is 2. So because you are subtracting 7 from v to get 2.5, you have to add 2.5 to 7 to get v. V=9.5
All of the centra angles in a regular polygon must add up to 360 degrees. Also, because you're told that it is a regular polygon, the "regular" indicates that all of the central angles will be the same. Divide 360 degrees by 18 degrees to get the number of central angles, which is the same as the number of sides. 360/18 = 20. Therefore, the polygon has 20 sides. Hope that helps!
