Answer:

<h3>4th answer is correct</h3>
Step-by-step explanation:

You have to factor and then get the x intercepts
I'm attaching the graph of the above function
You can do this by completing the square
x^2 - 14x + y^2 + 8 = 16
(x - 7)^2 - 49 + (y + 4)^2 - 16 = 16
(x - 7)^2 + (y + 4)^2 = 16 + 16 + 49 = 81
so the center is at (7 , -4) and radius = sqrt81 = 9
30-(11+(18-(48/8×2))+7)+15
= 30-(11+(18-12)+7)+15
= 30-(11+6+7)+15
= 30-24+15
= 21