# What is the standard form of the equation of a circle with center at (-3, 1) and through the point (2, 13)?

##### 1 Answer

(see below for discussion of alternate "standard form")

#### Explanation:

The "standard form of an equation for a circle" is

for a circle with center

Since we are given the center, we only need to compute the radius (using the Pythagorean Theorem)

So the equation of the circle is

Sometimes what is being asked for is the "standard form of the polynomial" and this is somewhat different.

The "standard form of the polynomial" is expressed as a sum of terms arranged with decreasing degrees set equal to zero.

If this is what your teacher is looking for you will need to expand and rearrange the terms: