You have seen an example of how to graph a circle if you are given its equation. If you have the equation of a circle, you should be able to identify its center and radius fairly easy. Are you ready to try on your own? In these practice exercises, identify the coordinates of the center and the length of the radius based on the equation you're given. Then, graph each circle on the coordinate plane.
Problem 1
Problem 2
Problem 3
Problem 4
What is the graph of this circle?
\(\mathsf{(x-2)^2 + (y-5)^2 = 16}\)
The center of this circle is (2,5). Its radius is 4.
What is the graph of this circle?
\(\mathsf{(x+1)^2 + (y-2)^2 = 25}\)
The center of this circle is (-1, 2). Its radius is 5.
What is the graph of this circle?
\(\mathsf{(x-6)^2 + (y+9)^2 = 4}\)
The center of this circle is (6,-9). Its radius is 2.
What is the graph of this circle?
\(\mathsf{(x+8)^2 + (y+2)^2 = 36}\)
The center of this circle is (-8, -2). Its radius is 6.
