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C2 help needed

A line, L, has equation y=mx and a circle, C, has equation
x^2+y^2-6x-4y+9=0

A) given that L is a tangent to C find the possible values of m

B) find the range of values of m, given that L intersects C in two distinct places.

C) find the range of values of m, given that L and C do not intersect.

For part A, I figured out one of the values of M would be 0, but can't find the other value, and I need help with parts B and C
Original post by Vorsah
A line, L, has equation y=mx and a circle, C, has equation
x^2+y^2-6x-4y+9=0

A) given that L is a tangent to C find the possible values of m

B) find the range of values of m, given that L intersects C in two distinct places.

C) find the range of values of m, given that L and C do not intersect.

For part A, I figured out one of the values of M would be 0, but can't find the other value, and I need help with parts B and C


Substitute in.

For (A), you need the discriminant to show a repeated root.

For (B), you need the discriminant to show that there are 2 distinct roots

For (C), you need the discriminant to show that there is no intersection (i.e ...)

Can you go from there? :smile:
(edited 11 years ago)

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