Hi everyone,

now I know this is easy peasy for you guys - but bear with me!

I'll write out the whole question first.

I completely understand parts a and b, but c has confused me a little. I've tried thinking about it (alot!) but I am just unsure as to what approach I need for c. It's only worth a couple of marks, so it should be fairly easy - but I'm not seeing what I need to do!

Could you point me in the right direction?

Thanks,

Sparky

now I know this is easy peasy for you guys - but bear with me!

I'll write out the whole question first.

Phew!7. A circle with centre C has equation \(x^{2}+y^{2}-4x+12y+15=0\).

a) Find:

i) the coordinates of C;

ii) the radius of the circle.

b) Explain why the circle lies entirely below the x-axis.

c) The point P with coordinates (5,k) lies outside the circle.

i) Show that \(PC^{2}=k^{2}+12k+45.\)

ii) Hence show that \(k^{2}+12k+20>0\)

iii) FInd the possible values of k.

I completely understand parts a and b, but c has confused me a little. I've tried thinking about it (alot!) but I am just unsure as to what approach I need for c. It's only worth a couple of marks, so it should be fairly easy - but I'm not seeing what I need to do!

Could you point me in the right direction?

Thanks,

Sparky

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