Question

Write the general conic form equation for a circle with center (3, -1) and radius of 5. x 2 + y 2 - 15 = 0 x 2 - 6x + y 2 + 2y - 15 = 0 x 2 - 6x + y 2 + 2y + 5 = 0

Answer 1

we know that
the equation of a circle in standard form is 
(x-h)²+(y-k)²=r²
(h,k) is the center----------> (3,-1)
r is the radius--------> r=5 units
(x-3)²+(y+1)²=25------> x²-6x+9+y²+2y+1=25---> x²-6x+y²+2y-15=0

the answer is
x 2 - 6x + y 2 + 2y - 15 = 0