Question

Obtain the equation of the circles with radius 5 cm and touching x-axis at the origin in general form

Answer 1

Given radius = 5 cm and the circle is touching x-axis

So centre will be (0, ± 5) and radius = 5

The equation of the circle with centre (0, ± 5) and radius 5 units is

(x – 0)² + (y ± 5)² = 5²

(i.e) x² + y² ± 10 y + 25 – 25 = 0

(i.e) x² + y² ± 10y = 0