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Lines in a circle

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1. Could someone guide me towards the answer:

Q) A chord of a circle passes through the points P(-2,-3) and Q(6,1). Find the equation of the diameter of the circle perpendicular to this chord.

I get that the gradient of the line perpendicular is the inverse reciprocal but I've just got mind block past that.
2. (Original post by SuchBants)
Could someone guide me towards the answer:

Q) A chord of a circle passes through the points P(-2,-3) and Q(6,1). Find the equation of the diameter of the circle perpendicular to this chord.

I get that the gradient of the line perpendicular is the inverse reciprocal but I've just got mind block past that.
The diameter is the perpendicular BISECTOR of any chord.
3. (Original post by SuchBants)
Could someone guide me towards the answer:

Q) A chord of a circle passes through the points P(-2,-3) and Q(6,1). Find the equation of the diameter of the circle perpendicular to this chord.

I get that the gradient of the line perpendicular is the inverse reciprocal but I've just got mind block past that.
Okay so you know the gradient of the diameter then. Now you can find the point through which the diameter must pass because the diameter must go through the middle of the chord. You can work out the co-ordinates of the middle of the chord. Then you have enough info for the line equation.

(Original post by ValerieKR)
The diameter is the perpendicular BISECTOR of any chord.
That really doesn't help in his situation, but I'm a bit fussed with the wording. Never mind, though.
4. (Original post by RDKGames)
That really doesn't help in his situation, but I'm a bit fussed with the wording. Never mind, though.
They know the gradient - bisector gives the constant.
5. (Original post by ValerieKR)
The diameter is the perpendicular BISECTOR of any chord.
Thank you, I wasn't aware of this

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