Understanding the Equation: (x - 2)^2 + (y + 3)^2 = 9
The equation (x - 2)^2 + (y + 3)^2 = 9 represents a circle in the coordinate plane. Let's break down why:
The Standard Form of a Circle
The general standard form of a circle's equation is:
(x - h)^2 + (y - k)^2 = r^2
Where:
- (h, k) represents the center of the circle.
- r represents the radius of the circle.
Analyzing Our Equation
Comparing our equation (x - 2)^2 + (y + 3)^2 = 9 to the standard form, we can identify the following:
- Center: (h, k) = (2, -3)
- Radius: r^2 = 9, so r = 3
Graphical Representation
This information allows us to easily plot the circle on a graph.
- Locate the Center: Start by marking the point (2, -3) on the coordinate plane.
- Draw the Radius: From the center, measure out a distance of 3 units in all directions (up, down, left, right).
- Sketch the Circle: Connect the points you marked in step 2 to form a smooth circle.
Key Takeaways
- The equation (x - 2)^2 + (y + 3)^2 = 9 describes a circle centered at (2, -3) with a radius of 3.
- Understanding the standard form of a circle's equation makes it easy to identify its center and radius.
- This information enables you to visually represent the circle on a graph.