Diameter of a circle endpoints P(0,0) Q(8,-4) what equation:

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Homework Help Overview

The discussion revolves around finding the equation of a circle given the endpoints of its diameter, specifically points P(0,0) and Q(8,-4). The subject area is analytic geometry.

Discussion Character

  • Exploratory, Problem interpretation

Approaches and Questions Raised

  • Participants discuss finding the midpoint of the diameter and the radius of the circle. There is an attempt to derive the equation of the circle based on these calculations.

Discussion Status

Multiple participants have shared similar calculations regarding the midpoint and radius, indicating a collaborative exploration of the problem. There is acknowledgment of the problem's context as homework-related, and participants are clarifying the appropriate section for the discussion.

Contextual Notes

Some participants express uncertainty about the categorization of the problem within the forum, indicating a potential lack of clarity in the subject area classification.

Jaco Viljoen
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Mod note: Moved from technical math section, so no template.
The diameter of a circle has endpoints P(0,0) and Q(8,-4) Find the equation:

First I will find the midpoint:
M(x,y)=(x1+x2)/2,(y1+y2)/2
=8/2,-4/2)
M(x,y)=(-4,-2)

Then I will find the radius:
r^2=(x-h)^2+(y-k)^2
r^2=(0-4)^2+(0+2)^2
r^2=16+4
r^2=20

so
(x-4)^2+(y+2)^2=20
 
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Jaco Viljoen said:
The diameter of a circle has endpoints P(0,0) and Q(8,-4) Find the equation:

First I will find the midpoint:
M(x,y)=(x1+x2)/2,(y1+y2)/2
=8/2,-4/2)
M(x,y)=(-4,-2)

Then I will find the radius:
r^2=(x-h)^2+(y-k)^2
r^2=(0-4)^2+(0+2)^2
r^2=16+4
r^2=20

so
(x-4)^2+(y+2)^2=20
That's what I get, as well.

BTW, this looks like homework, or at least a problem from a textbook, so I'm moving it to the homework section.
 
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Thank you Mark,
I wasn't sure if I should post under pre calculus as I couldn't find any geometry there, thanks again.
 
This would come under the heading of analytic geometry, so the Precalc section is the right place for it.
 
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