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Co-ordinate Geometry MEI C1 Help

A(2,-1) and B(4,3) are two points on a circle with centre (1,2). What is the distance of the chord from the centre of the circle?
A step to step solution thanks
Original post by davies4phones
A(2,-1) and B(4,3) are two points on a circle with centre (1,2). What is the distance of the chord from the centre of the circle?
A step to step solution thanks


We don't give step-by-step solutions here. Have a go first, show us what you've done and where you're going wrong, then we'll be able to guide you in the right direction.

As for a place to start, sketch a small diagram of the circle, chord and the centre. I assume it wants the shortest distance from the chord to the centre which would mean you need to find a point on the chord (A) which makes OA perpendicular to the chord, then find the distance of this line.
you need to find the midpoint of the chord then using the equation ( which is probably in your book) you can find the distance between the two points
Original post by RDKGames
We don't give step-by-step solutions here. Have a go first, show us what you've done and where you're going wrong, then we'll be able to guide you in the right direction.

As for a place to start, sketch a small diagram of the circle, chord and the centre. I assume it wants the shortest distance from the chord to the centre which would mean you need to find a point on the chord (A) which makes OA perpendicular to the chord, then find the distance of this line.


So the midpoint of the chord is (3,1)
so then do I need to find out the distance between (1,2) and (3,1) using the distance formula involving pythag
Original post by davies4phones
So the midpoint of the chord is (3,1)
so then do I need to find out the distance between (1,2) and (3,1) using the distance formula involving pythag


That's right.
Original post by CrystalSalvatore
you need to find the midpoint of the chord then using the equation ( which is probably in your book) you can find the distance between the two points


Thank you
Original post by RDKGames
That's right.


Thank you!

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