A circle has its center at (-1,2) and a radius of 3 units. What is the equation of the circle?

Pythagorean Theorem is for triangles not circles. 

The equation of a circle is (x - h)² + (y - k)² = radius² where (h, k) is the center.

Plug in your given information and simplify.

(x - (- 1))² + (y - 2)² = (3)²

(x + 1)² + (y - 2)² = 9 is your equation. 

(x+1)^2 + (y-2)^2 = 9

Step-by-step explanation:

We can write the equation of a circle as

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

Where (h,k) is the center and r is the radius

(x--1)^2 + (y-2)^2 = 3^2

(x+1)^2 + (y-2)^2 = 9

a variable is any characteristics, number, or quantity that can be measured or counted. a variable may also be called a data item. hope i !