+7 would be the answer i believe
Let x = your number.
6x = x^2 - 27. Subtract 6x from each side.
0 = x^2 - 6x - 27. Factor
0 = (x-9) (x+3). Set each term equal to zero
(x+3) = 0. Subtract 3 from each side.
x = -3. This is the negative solution.
(x-9) = 0. Add 9 to each side.
x = 9. This is the positive solution.
Standard form for circle with radius r and center (h,k) is
(x-h)^2+(y-k)^2=r^2
r=36
center at -2,-7
(x-(-2))^2+(y-(-7))^2=36^2
(x+2)^2+(y+7)^2=1296
firts option
You can't change the sum by changing the grouping. Any way you cut it, you will always get 226, as you only have addition operations, and the commutative property [a+(b+c)=(a+b)+c] means that the sum will always be the same.