Question

Find the equation of the circle with centre (0, 2) and radius 2

Answer 1

The equation of a circle with centre (h, k) and radius r is given as

(x­ – h)² + (y ­– k)² = r²

It is given that centre (h, k) = (0, 2) and radius (r) = 2.

Therefore, the equation of the circle is

(x – 0)² + (y – 2)² = 2²

x² + y² + 4 ­– 4 y = 4

x² + y² ­– 4y = 0