Examination Question (1 Viewer)

[wiliaamnguuyen]

Can anyone do this question (it's a last question in the exam).
Question:
Answer:

I'd be grateful if anyone can help me, I think I can find what C1 is but having troubles finding C2

 

[Kaido]

First let's re-write in general form:
(x-3)^2 + (y+k)^2=k^2-3k+9

For C1: Centre = (3,-k). Sub this into x-3y=0 -> yielding k=-1
For C2: Centre = (3,-k). Therefore we want to find y-coordinate. But y-coord is also = radius (as the circle touches the x-axis)
Therefore k=Sqrt (k^2-3k+9)
Square both sides and solve for k: k=3

 

[porcupinetree]

Cool question

https://imgur.com/2OK89cA

 

[braintic]

First let's re-write in general form

Actually, the form the equation was given in originally is general form.

 

[Kaido]

Actually, the form the equation was given in originally is general form.

Tis true