# What is the standard form of the equation of a circle with centre is at point (5,8) and which passes through the point (2,5)?

##### 2 Answers

#### Explanation:

standard form of a circle is

where (a , b ) is the centre of the circle and r = radius.

in this question the centre is known but r is not. To find r , however ,

the distance from the centre to the point ( 2 , 5 ) is the radius . Using

the distance formula will allow us to find in fact

now using (2 , 5 ) =

then

equation of circle :

.

I found:

#### Explanation:

The distance

We can evaluate it using:

So:

Now you can use the general form of the equation of a circle with centre at

And: