Question

Find the equation of the circle whose center and radius are given. center (0, 8), radius = 8

Answer 1

The equation of circle is
`x^2+y^2-16x=0`

Explanation:

Given: Centre of circle: (0,8) and Radius = 8

Formula: Equation of circle if centre (h,k) and radius r

`(x-h)^2+(y-k)^2=r^2`

Where, (h,k)-> (0,8) and r=8

Now, we will put the value of centre and radius into formula

Equation of circle:

`(x-0)^2+(y-8)^2=8^2`

`x^2+(y-8)^2=64`

In expanded form equation of circle.

`x^2+y^2-16x+64=64`

`x^2+y^2-16x=0`

Hence, The equation of circle is
`x^2+y^2-16x=0`

Answer 2

x^2 + (y-8)^2 = 64

use the center for the left side of the equation. X goes with X, Y goes with Y. Always do the opposite sign. The equation is equal to the radius squared


Hope this helped : )