Finding the Equation of a Circle Given Specific Conditions

  • MHB
  • Thread starter mathdad
  • Start date
  • Tags
    Circle
In summary, to determine the equation of the circle that satisfies the given conditions, you will need to first find the centers of the two given circles. To do this, you will need to rewrite the circles in the form (x-h)^2+(y-k)^2=r^2, completing the square for both x and y. Once you have the coordinates of the centers, you can find the midpoint of the line segment joining them, which will be the center of the desired circle. From there, you can use the standard form equation for a circle (x-h)^2+(y-k)^2=r^2 to write the equation of the circle that passes through (-4, 1) and has its center at the midpoint of the
  • #1
mathdad
1,283
1
Determine the equation of the circle that satisfies the given conditions. Write the equation in standard form.

The circle passes through (-4, 1) and its center is the midpoint of the line segment joining the centers of the two circles x^2 + y^2 - 6x - 4y + 12 = 0 and x^2 + y^2 - 14x + 47 = 0.

I would like the steps for me to solve this interesting problem.
 
Mathematics news on Phys.org
  • #2
I would begin by determining the centers of the two given circles, so that we can determine the mid-point of the line segment joining those centers. So, rewrite the two given circles in the form:

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

What do you get?
 
  • #3
MarkFL said:
I would begin by determining the centers of the two given circles, so that we can determine the mid-point of the line segment joining those centers. So, rewrite the two given circles in the form:

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

What do you get?

Must I complete the square for both circles?
 
  • #4
RTCNTC said:
Must I complete the square for both circles?

Yes, for both circles you want to complete the square for both x and y to get them in the desired form from which you can read off the coordinates of the centers. :D
 
  • #5
MarkFL said:
Yes, for both circles you want to complete the square for both x and y to get them in the desired form from which you can read off the coordinates of the centers. :D

Good. I will try later.
 

FAQ: Finding the Equation of a Circle Given Specific Conditions

How do you determine the equation of a circle?

To determine the equation of a circle, you will need to know the coordinates of the center of the circle (h,k) and the radius (r). The equation is (x-h)^2 + (y-k)^2 = r^2, with (h,k) being the coordinates of the center and r being the radius.

What information do I need to determine the equation of a circle?

You will need to know the coordinates of the center of the circle and the radius. These can be obtained from a graph or given in a problem.

Can I determine the equation of a circle if I only know three points on the circle?

Yes, you can determine the equation of a circle if you know three points on the circle. You will need to use the equation (x-h)^2 + (y-k)^2 = r^2 and plug in the coordinates of each point to solve for h, k, and r.

How is the equation of a circle related to its graph?

The equation (x-h)^2 + (y-k)^2 = r^2 represents a circle with center (h,k) and radius r. The graph of this equation will be a circle with its center at the point (h,k) and a radius of r.

Can the equation of a circle be written in different forms?

Yes, the equation of a circle can be written in different forms. The standard form is (x-h)^2 + (y-k)^2 = r^2, but it can also be written as (x-a)^2 + (y-b)^2 = c, where (a,b) is the center of the circle and c = r^2. It can also be written in general form as x^2 + y^2 + Dx + Ey + F = 0, where D, E, and F are constants.

Similar threads

Replies
6
Views
2K
Replies
4
Views
1K
Replies
6
Views
1K
Replies
4
Views
1K
Replies
2
Views
995
Replies
8
Views
2K
Replies
3
Views
1K
Back
Top