(x + 2 )² + (y - 4)² = 36 ← is the equation of the circle
the equation of a circle in standard form is (x - a)² + (y - b)² = r²
where (a, b) are the coordinates of the centre and r is the radius
here (a, b ) =(- 2, 4) and r = 6
(x + 2)² + ( y - 4 )² = 36