The answer is C: first add 2 both sides then divide both sides by -5.
Consider,

. Let's say

then the problem reduces to

. (Do you understand this step?)
So then replacing a again with our definition we get,

.
Answer:
its 12
Step-by-step explanation:
Answer:
150 kids
Step-by-step explanation:
If 60 kids is 40% of the total kids, we can add another 60 to get 80% and then half of 60 (30) to bring the total up to 100% of the kids.
100 * pi = pi * r^2
Pi cancels on both sides of the equation
So... 100= r^2
= radius is 10