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    Given that the line with the equation y=x+k is a tangent to the circle x^2+y^2=25

    Find the 2 possible values of K

    Need help getting started with this question
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    (Original post by Vorsah)
    Given that the line with the equation y=x+k is a tangent to the circle x^2+y^2=25

    Find the 2 possible values of K

    Need help getting started with this question
    Substitute in. Remember that you have a tangent if the discriminant is zero
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    (Original post by Vorsah)
    Given that the line with the equation y=x+k is a tangent to the circle x^2+y^2=25

    Find the 2 possible values of K

    Need help getting started with this question
    Do you have the answer to this question?

    I got +- 50 as k by solving the equations simultaneously and then letting b^2 - 4ac be 0
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    (Original post by Lunch_Box)
    Do you have the answer to this question?

    I got +- 50 as k by solving the equations simultaneously and then letting b^2 - 4ac be 0
    Check your working, that isn't right but you are close!
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    (Original post by Lunch_Box)
    Do you have the answer to this question?

    I got +- 50 as k by solving the equations simultaneously and then letting b^2 - 4ac be 0
    \displaystyle k \neq \pm \ 50

    Probably a typo
 
 
 
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