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Circles question in higher maths homework

Can anyone help me answer this question, or just or the steps to do this, not too sure and hope you can understand it :smile:


The line
y +2x=k
where
k > 0 is a tangent to the circle with equation
x squared + y squared -2x -4 (circle eqn)
a) Find the value of k.
b) Deduce the coordinates of the point of contact.
(edited 8 years ago)
Sorry you've not had any responses about this. :frown:

Why not try posting in a specific subject forum- you might have more luck there.

Here's a link to our subject forum which should help get you more responses. :redface:

:h:
Original post by Misshussain23
Can anyone help me answer this question, or just or the steps to do this, not too sure and hope you can understand it :smile:


The line
y +2x=k
where
k > 0 is a tangent to the circle with equation
x squared + y squared -2x -4 (circle eqn)
a) Find the value of k.
b) Deduce the coordinates of the point of contact.


If its a tangent, then the circle and the line only intersect once.

What you can hence do is form an equation that will allow you to find the coordinates of intersection in terms of k and use your knowledge of the discriminant to work out what k is.

Have a go :smile:
Original post by kingaaran
If its a tangent, then the circle and the line only intersect once.

What you can hence do is form an equation that will allow you to find the coordinates of intersection in terms of k and use your knowledge of the discriminant to work out what k is.

Have a go :smile:


You're a savage dude. You're only ever on this site late at night, do you sleep?
Original post by StopBanningDuck
You're a savage dude. You're only ever on this site late at night, do you sleep?


My night is your day :wink:
Original post by kingaaran
My night is your day :wink:


That is some real vampire s h i t right there :afraid:
Original post by StopBanningDuck
That is some real vampire s h i t right there :afraid:


Haha, what a lad :tongue:


Posted from TSR Mobile
:wink:. I meant to ask you this a long time ago, but mods kept banning me for no reason, so I had to chose the right time to resurrect myself. How did your Cambrige interview go?
Original post by StopBanningDuck
:wink:. I meant to ask you this a long time ago, but mods kept banning me for no reason, so I had to chose the right time to resurrect myself. How did your Cambrige interview go?


Meh, one was decent, the other was horrible.

As you might know, I didn't get an offer. But idm, now I'm going to do maths and physics at Warwick and it equally excites me

:smile:


Posted from TSR Mobile
Original post by kingaaran
Meh, one was decent, the other was horrible.

As you might know, I didn't get an offer. But idm, now I'm going to do maths and physics at Warwick and it equally excites me

:smile:


Posted from TSR Mobile


Their lost, I guess. The interviews were not formal right? So, they asked you questions relating to maths?
Original post by StopBanningDuck
Their lost, I guess. The interviews were not formal right? So, they asked you questions relating to maths?


Yeah, just maths


Posted from TSR Mobile
Original post by kingaaran
If its a tangent, then the circle and the line only intersect once.

What you can hence do is form an equation that will allow you to find the coordinates of intersection in terms of k and use your knowledge of the discriminant to work out what k is.

Have a go :smile:


Thanks so much! It makes much more sense now :smile:

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