Give the Center and Radius of the Circle Described by the Equation and Graph the Equation

Oct 13, 2025 by wbrum.org 50 views

Give the Center and Radius of the Circle Described by the Equation and Graph the Equation

In mathematics, a circle is a set of points that are equidistant from a central point called the center. The equation of a circle can be written in the form $(x - h)^2 + (y - k)^2 = r^2$ , where $(h, k)$ is the center of the circle and $r$ is the radius. In this article, we will give the center and radius of the circle described by the equation $x^2 + y^2 = 36$ and graph the equation. We will also use the graph to identify the relation's domain and range.

The Equation of a Circle

The equation of a circle can be written in the form $(x - h)^2 + (y - k)^2 = r^2$ , where $(h, k)$ is the center of the circle and $r$ is the radius. To find the center and radius of the circle described by the equation $x^2 + y^2 = 36$ , we need to rewrite the equation in the standard form.

Rewriting the Equation

To rewrite the equation $x^2 + y^2 = 36$ in the standard form, we need to complete the square for both $x$ and $y$ . We can do this by adding and subtracting the square of half the coefficient of $x$ and $y$ .

import sympy as sp

# Define the variables
x, y = sp.symbols('x y')

# Define the equation
equation = x**2 + y**2 - 36

# Complete the square for x and y
completed_square = (x - 0)**2 + (y - 0)**2 - 36

# Print the completed square
print(completed_square)

The completed square is $(x - 0)^2 + (y - 0)^2 = 36$ . This means that the center of the circle is $(0, 0)$ and the radius is $\sqrt{36} = 6$ .

Graphing the Equation

To graph the equation $x^2 + y^2 = 36$ , we can use a graphing calculator or a computer algebra system. The graph of the equation is a circle with center $(0, 0)$ and radius $6$ .

import matplotlib.pyplot as plt
import numpy as np

# Define the variables
x = np.linspace(-10, 10, 400)
y = np.sqrt(36 - x**2)

# Create the plot
plt.plot(x, y)
plt.plot(x, -y)
plt.gca().set_aspect('equal', adjustable='box')
plt.show()

The graph of the equation is a circle with center $(0, 0)$ and radius $6$ .

Domain and Range

The domain of the relation is the set of all possible input values of $x$ and $y$ . Since the equation is a circle, the domain is all real numbers except for the center of the circle.

The range of the relation is the set of all possible output values of $x$ and $y$ . Since the equation is a circle, the range is all real numbers except for the center of the circle.

In this article, we gave the center and radius of the circle described by the equation $x^2 + y^2 = 36$ and graphed the equation. We also used the graph to identify the relation's domain and range. The center of the circle is $(0, 0)$ and the radius is $6$ . The domain of the relation is all real numbers except for the center of the circle, and the range is all real numbers except for the center of the circle.

[1] "Circle" by Math Open Reference. Retrieved February 2023.
[2] "Graphing Circles" by Purplemath. Retrieved February 2023.

The equation $x^2 + y^2 = 36$ describes a circle with center $(0, 0)$ and radius $6$ . The graph of the equation is a circle with center $(0, 0)$ and radius $6$ . The domain of the relation is all real numbers except for the center of the circle, and the range is all real numbers except for the center of the circle.

What do you think about the equation $x^2 + y^2 = 36$ ? Do you have any questions or comments about the article? Please feel free to ask or share your thoughts in the discussion section below.
Q&A: Understanding the Equation of a Circle

In our previous article, we discussed the equation of a circle and how to find the center and radius of a circle described by the equation $x^2 + y^2 = 36$ . We also graphed the equation and identified the relation's domain and range. In this article, we will answer some frequently asked questions about the equation of a circle.

Q: What is the equation of a circle?

A: The equation of a circle can be written in the form $(x - h)^2 + (y - k)^2 = r^2$ , where $(h, k)$ is the center of the circle and $r$ is the radius.

Q: How do I find the center and radius of a circle described by the equation?

A: To find the center and radius of a circle described by the equation, you need to rewrite the equation in the standard form by completing the square for both $x$ and $y$ . The center of the circle is the point $(h, k)$ and the radius is the square root of the constant term on the right-hand side of the equation.

Q: What is the graph of the equation of a circle?

A: The graph of the equation of a circle is a circle with center $(h, k)$ and radius $r$ . The graph is a closed curve that is symmetric about the center of the circle.

Q: What is the domain and range of the equation of a circle?

A: The domain of the equation of a circle is all real numbers except for the center of the circle. The range of the equation of a circle is all real numbers except for the center of the circle.

Q: How do I graph the equation of a circle?

A: To graph the equation of a circle, you can use a graphing calculator or a computer algebra system. You can also use the equation to find the coordinates of the center and radius of the circle and then plot the circle using these coordinates.

Q: What are some common mistakes to avoid when working with the equation of a circle?

A: Some common mistakes to avoid when working with the equation of a circle include:

Not completing the square for both $x$ and $y$ when rewriting the equation in the standard form.
Not identifying the center and radius of the circle correctly.
Not graphing the equation correctly.
Not identifying the domain and range of the equation correctly.

Q: How do I use the equation of a circle in real-world applications?

A: The equation of a circle has many real-world applications, including:

Calculating the area and circumference of a circle.
Finding the center and radius of a circle.
Graphing the equation of a circle.
Identifying the domain and range of the equation of a circle.

In this article, we answered some frequently asked questions about the equation of a circle. We discussed how to find the center and radius of a circle described by the equation, how to graph the equation, and how to identify the domain and range of the equation. We also discussed some common mistakes to avoid when working with the equation of a circle and how to use the equation in real-world applications.

[1] "Circle" by Math Open Reference. Retrieved February 2023.
[2] "Graphing Circles" by Purplemath. Retrieved February 2023.

Do you have any questions or comments about the article? Please feel free to ask or share your thoughts in the discussion section below.

Q: What is the equation of a circle?
A: The equation of a circle can be written in the form $(x - h)^2 + (y - k)^2 = r^2$ , where $(h, k)$ is the center of the circle and $r$ is the radius.
Q: How do I find the center and radius of a circle described by the equation?
A: To find the center and radius of a circle described by the equation, you need to rewrite the equation in the standard form by completing the square for both $x$ and $y$ .
Q: What is the graph of the equation of a circle?
A: The graph of the equation of a circle is a circle with center $(h, k)$ and radius $r$ .
Q: What is the domain and range of the equation of a circle?
A: The domain of the equation of a circle is all real numbers except for the center of the circle. The range of the equation of a circle is all real numbers except for the center of the circle.