What is the standard form of the equation of a circle with center of a circle is at (-15,32) and passes through the point (-18,21)?

1 Answer
Nov 14, 2015

(x+15)2+(y32)2=130

Explanation:

The standard form of a circle centred at (a,b) and having radius r is (xa)2+(yb)2=r2.

So in this case we have the centre, but we need to find the radius and can do so by finding the distance from the centre to the point given :

d((15,32);(18,21))=(18(15))2+(2132)2=130

Therefore the equation of the circle is

(x+15)2+(y32)2=130