# Precalculus Examples

,

Use the distance formula to determine the distance between the two points.

Substitute the actual values of the points into the distance formula.

Simplify.

Multiply by .

Subtract from .

Remove parentheses around .

Raise to the power of .

Multiply by .

Add and .

Remove parentheses around .

Raise to the power of .

Add and .

Rewrite as .

Factor out of .

Rewrite as .

Pull terms out from under the radical.

is the equation form for a circle with radius and as the center point. In this case, and the center point is . The equation for the circle is .

The circle equation is .