Answer:
see explanation
Step-by-step explanation:
the equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
To obtain this form use the method of completing the square on both the x and y terms
rearranging
x² + 6x + y² - 4y = 12
x² + 2(3)x + 9 + y² + 2(- 2)y + 4 = 12 + 9 + 4
(x + 3)² + (y - 2)² = 25 ← in standard form
with centre = (- 3, 2) and r = [tex]\sqrt{25}[/tex] = 5
