Skip to content Skip to sidebar Skip to footer

Discover the Radius of a Circle: x² + y² + 8x - 6y + 21 = 0 | 2-5 Units!

What Is The Radius Of A Circle Whose Equation Is X2+Y2+8x−6y+21=0? 2 Units 3 Units 4 Units 5 Units

The radius of the circle with equation x^2 + y^2 + 8x - 6y + 21 = 0 is 2 units, 3 units, 4 units, or 5 units.

The radius of a circle plays a vital role in understanding its properties and characteristics. In the case of a circle with the equation x^2 + y^2 + 8x - 6y + 21 = 0, determining its radius becomes an intriguing mathematical challenge. By unlocking the secrets hidden within this equation, we can unravel the exact measure of the radius, which holds the key to comprehending the circle's size and reach. To embark on this fascinating journey, let us embark on a quest to find answers by employing various techniques and calculations.

When it comes to measuring the radius of a circle, a crucial tool is the equation that defines its geometric shape. In this case, the given equation x^2 + y^2 + 8x - 6y + 21 = 0 provides us with valuable clues. To extract the radius from this equation, we need to employ algebraic techniques such as completing the square or converting it into a more recognizable form. By skillfully manipulating the equation, we will be able to transform it into a more manageable and revealing shape, ultimately guiding us towards the elusive radius value.

Now, armed with mathematical prowess and determination, let us dive into the depths of this intriguing equation to discover the hidden radius. As we embark on this intellectual adventure, every step we take will be carefully guided by logic and reason. By applying our knowledge of circles and their equations, we will soon uncover the true measure of the radius, allowing us to unlock the circle's mysteries and gain a deeper understanding of its nature.

In our pursuit of knowledge, we shall not stop at just one possibility. Instead, we shall explore multiple scenarios, considering different values for the radius. By examining the equation x^2 + y^2 + 8x - 6y + 21 = 0 through the lens of various radius lengths, such as 2 units, 3 units, 4 units, and 5 units, we can compare and contrast the resulting circles. This comparative analysis will provide us with valuable insights into the relationship between the equation and the circle's size, enabling us to draw meaningful conclusions about its properties.

Introduction

In mathematics, the equation of a circle can be represented in the form (x - h)^2 + (y - k)^2 = r^2, where (h, k) represents the coordinates of the center and r represents the radius. In this article, we will explore how to determine the radius of a circle given its equation. Specifically, we will analyze the equation x^2 + y^2 + 8x - 6y + 21 = 0 and calculate its radius for different values.

Finding the Center of the Circle

To determine the radius of the circle, we first need to find the coordinates of its center. The general equation of a circle can be rearranged to obtain the center's coordinates. In our given equation x^2 + y^2 + 8x - 6y + 21 = 0, we can group the terms involving x and y together. Rearranging the equation, we get (x^2 + 8x) + (y^2 - 6y) = -21. Completing the square for both x and y, we can rewrite the equation as (x^2 + 8x + 16) + (y^2 - 6y + 9) = -21 + 16 + 9. Simplifying further, we have (x + 4)^2 + (y - 3)^2 = 4.

Understanding the Standard Form

We have now obtained the equation of the circle in standard form, (x - h)^2 + (y - k)^2 = r^2, where (h, k) represents the center of the circle and r represents its radius. Comparing this with our equation (x + 4)^2 + (y - 3)^2 = 4, we can conclude that the center of the circle is (-4, 3) since (h, k) = (-4, 3). Now, let's proceed to calculate the radius for different values.

Calculating the Radius for 2 Units

Using the equation (x + 4)^2 + (y - 3)^2 = 4, we can substitute r = 2 to determine the radius for 2 units. Plugging in r = 2, we have (-4 + 2)^2 + (3)^2 = 4. Simplifying further, we get (-2)^2 + 3^2 = 4, which results in 4 + 9 = 13. Therefore, when the radius is 2 units, the equation x^2 + y^2 + 8x - 6y + 21 = 0 represents a circle with a radius of √13 units.

Calculating the Radius for 3 Units

Similarly, let's calculate the radius for 3 units using the equation (x + 4)^2 + (y - 3)^2 = 4. By substituting r = 3, we obtain (-4 + 3)^2 + (3)^2 = 4. Simplifying this equation, we get (-1)^2 + 3^2 = 4, which leads to 1 + 9 = 10. Thus, when the radius is 3 units, the equation x^2 + y^2 + 8x - 6y + 21 = 0 describes a circle with a radius of √10 units.

Calculating the Radius for 4 Units

Continuing our calculations, let's determine the radius for 4 units using the equation (x + 4)^2 + (y - 3)^2 = 4. Substituting r = 4, we find (-4 + 4)^2 + (3)^2 = 4. Simplifying this equation, we obtain (0)^2 + 3^2 = 4, which results in 9 = 4. However, this is not a valid solution since the left-hand side is greater than the right-hand side. Therefore, there is no circle with a radius of 4 units that satisfies the given equation.

Calculating the Radius for 5 Units

Lastly, let's calculate the radius for 5 units using the equation (x + 4)^2 + (y - 3)^2 = 4. Substituting r = 5, we find (-4 + 5)^2 + (3)^2 = 4. Simplifying this equation, we obtain (1)^2 + 3^2 = 4, which leads to 1 + 9 = 10. Thus, when the radius is 5 units, the equation x^2 + y^2 + 8x - 6y + 21 = 0 represents a circle with a radius of √10 units.

Conclusion

In conclusion, we have explored the process of determining the radius of a circle given its equation x^2 + y^2 + 8x - 6y + 21 = 0. By rearranging the equation into standard form and comparing it with the general equation of a circle, we found that the center of the circle is (-4, 3). Subsequently, we calculated the radius for different values, obtaining √13 units for a radius of 2 units and √10 units for radii of 3 and 5 units. However, there is no valid solution for a radius of 4 units. Understanding such calculations allows us to comprehend the properties and characteristics of circles represented by specific equations.

Introduction:

Understanding the radius of a circle defined by the equation x^2 + y^2 + 8x - 6y + 21 = 0 is crucial in comprehending its properties and characteristics. By analyzing the equation and applying mathematical techniques, we can determine the radius and gain valuable insights into the circle's position, center, and graphical representation.

Analysis with a radius of 2 units:

When evaluating the equation x^2 + y^2 + 8x - 6y + 21 = 0, we find that it represents a circle with a radius of 2 units. By substituting this value into the equation, we can solve for x and y to identify the points on the circle's circumference. This analysis allows us to visualize the circle's shape and understand how it relates to other geometric elements.

Analysis with a radius of 3 units:

Continuing our investigation, we explore the equation x^2 + y^2 + 8x - 6y + 21 = 0 to uncover a circle with a radius of 3 units. By substituting this radius value into the equation and solving for x and y, we can determine the specific coordinates of the points lying on the circle's circumference. This analysis provides us with a deeper understanding of the circle's size and position within the Cartesian plane.

Analysis with a radius of 4 units:

Moving forward, we examine the equation x^2 + y^2 + 8x - 6y + 21 = 0 to ascertain the existence of a circle with a radius of 4 units. By plugging in this radius value and solving for x and y, we can obtain the precise coordinates of the points forming the circle's boundary. This analysis allows us to further explore how the circle expands or contracts as its radius varies.

Analysis with a radius of 5 units:

Continuing our exploration, we delve into the equation x^2 + y^2 + 8x - 6y + 21 = 0 to determine if there is a circle with a radius of 5 units. By substituting this value into the equation and solving for x and y, we can identify the coordinates of the points that lie on the circle's circumference. This analysis aids us in comprehending the circle's size and how it relates to other geometric elements in the plane.

Calculation of the radius:

To calculate the precise radius of the circle defined by x^2 + y^2 + 8x - 6y + 21 = 0, we employ various mathematical techniques. By rearranging the equation into the standard form of a circle, (x - h)^2 + (y - k)^2 = r^2, we can compare the coefficients to determine the values of h, k, and r. These calculations enable us to find the exact radius of the circle and understand its relationship to the given equation.

Interpretation of the equation's constants:

Decoding the role of the constants (8, -6, 21) in the equation x^2 + y^2 + 8x - 6y + 21 = 0 is vital for better comprehending the circle's characteristics. The constant terms affect the positioning and size of the circle, while the coefficients of x and y influence its center and radius. By analyzing these constants, we can gain deeper insights into the circle's properties and how they are represented algebraically.

Determining the circle's center:

Identifying the coordinates of the circle's center within the equation x^2 + y^2 + 8x - 6y + 21 = 0 is crucial for understanding its position on the Cartesian plane. By rearranging the equation, we can extract the values of h and k in the standard form (x - h)^2 + (y - k)^2 = r^2. These coordinates provide valuable information about the circle's location and allow us to visualize its relationship with other geometric elements.

Investigating the circle's position relative to the origin:

In our analysis of the equation x^2 + y^2 + 8x - 6y + 21 = 0, we examine whether the circle is centered at the origin or positioned elsewhere on the plane. By comparing the coordinates of the center with the origin (0, 0), we can determine if the circle is concentric or offset from the origin. This investigation helps us understand how the circle interacts with the Cartesian plane and other geometric figures.

Possible graphical representation:

To better comprehend the properties of the circle defined by x^2 + y^2 + 8x - 6y + 21 = 0, it is helpful to consider its graphical representation. By plotting the circle on a Cartesian plane, we can visualize its shape, size, and position relative to other elements. This graphical representation aids in understanding the circle's characteristics and facilitates further analysis and exploration.

Given the equation of a circle, X^2 + Y^2 + 8x - 6y + 21 = 0, we are tasked with finding the radius of this circle. Let's break down the process step by step:

  1. First, we need to rewrite the equation in standard form, which is (x - h)^2 + (y - k)^2 = r^2, where (h, k) represents the center of the circle and r represents the radius.
  2. To achieve this, we group the terms containing x and y together: x^2 + 8x + y^2 - 6y = -21.
  3. Next, we complete the square for both x and y terms. To complete the square for x, we take half of the coefficient of x, which is 8, and square it: (8/2)^2 = 16.
  4. We add this value, 16, to both sides of the equation: x^2 + 8x + 16 + y^2 - 6y = -21 + 16.
  5. Similarly, we complete the square for the y terms. Half of the coefficient of y is -6, and squaring it gives us (-6/2)^2 = 9.
  6. Adding this value, 9, to both sides of the equation: x^2 + 8x + 16 + y^2 - 6y + 9 = -21 + 16 + 9.
  7. Simplifying the equation further: (x + 4)^2 + (y - 3)^2 = 4.

Now that we have the equation in standard form, we can easily identify the center and radius of the circle. Comparing it to the standard form, we see that the center of the circle is at (-4, 3), as (h, k) = (-4, 3).

The radius, denoted by r, is the square root of the value on the right side of the equation, which is 4. Taking the square root of 4 gives us a radius of 2 units.

Therefore, the radius of the circle described by the equation x^2 + y^2 + 8x - 6y + 21 = 0 is 2 units.

Thank you for visiting our blog and taking the time to read about the radius of a circle with the equation X2+Y2+8x−6y+21=0. In this closing message, we will provide you with a comprehensive explanation of the radius for different units. So, let's dive in!

Firstly, when it comes to determining the radius of a circle, it is essential to understand the general form of its equation. In this case, the equation X2+Y2+8x−6y+21=0 represents a circle in standard form, where the coefficients of X2 and Y2 are both 1. To find the center of the circle, we need to complete the square by rearranging the equation as follows:

X2+8x+Y2−6y=-21

(X2+8x+16)+(Y2−6y+9)=-21+16+9

(X+4)2+(Y−3)2=4

Now that we have the equation in its standard form, (X−h)2+(Y−k)2=r2, we can determine the radius. By comparing the equation to the standard form, we find that the center of the circle is at (-4, 3), and the radius squared is equal to 4. Therefore, the radius is either 2 or -2 units.

It's worth noting that the radius of a circle cannot be negative, as it represents the distance from the center to any point on the circle. Thus, we disregard the negative value and conclude that the radius of the circle is 2 units.

In summary, the circle with the equation X2+Y2+8x−6y+21=0 has a radius of 2 units. We hope this explanation has provided you with a clear understanding of how to determine the radius of a circle given its equation. If you have any further questions or need additional assistance, feel free to leave a comment below. Happy math-solving!

What Is The Radius Of A Circle Whose Equation Is X^2+Y^2+8x−6y+21=0?

1. Calculation with Explanation:

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

Let's rearrange the given equation to match this form:

  • x^2 + 8x + y^2 - 6y + 21 = 0
  • (x^2 + 8x) + (y^2 - 6y) = -21
  • Completing the square for x: (x^2 + 8x + 16) + (y^2 - 6y) = -21 + 16
  • Completing the square for y: (x^2 + 8x + 16) + (y^2 - 6y + 9) = -21 + 16 + 9
  • (x + 4)^2 + (y - 3)^2 = 4

Comparing this equation with the standard form, we can see that the center of the circle is (-4, 3) and the radius of the circle is √4 = 2 units.

Answer:

The radius of the circle whose equation is x^2 + y^2 + 8x − 6y + 21 = 0 is 2 units.