Year 12s: what will be the first way you research your future options? >>

C1 question help

Can someone explain part (ii) to me?
I keep on getting radius as just root85/2

and also part three please

Thanks so much

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Reply 1

B_9710

Original post by greys-anatomy

Can someone explain part (ii) to me?
I keep on getting radius as just root85/2

and also part three please

Thanks so much

Yore correct for part (ii) but the mark scheme agrees with you anyway.
For (iii) you have to find the intersection of a line perpendicular to the circle at point B. The intersections of this line and the circle are at B and D.
[Hint: use the centre of circle found in part ii to find equation of line and therefore coordinates of D.]

Reply 2

Sirelis

what exam board is this :O