(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

You have a circle with the equation x[tex]^{2}[/tex] + (y + 1)[tex]^{2}[/tex] = 1. You can draw to two tangent lines to that circle that intersect the point (0,1) What are the equations of these lines? And you can't use any calculus, derivatives and the like.

2. Relevant equations

y=mx+b

quadratic formula

x[tex]^{2}[/tex] + (y + 1)[tex]^{2}[/tex] = 1

3. The attempt at a solution

Well you can begin by knowing that the lines y-int will be 1 so y=mx+1. Then you can solve the equation for the circle for y which gives you y = -1 [tex]\pm[/tex] [tex]\sqrt{1-x^{2}}[/tex]. Then you can set that equation equal to 0 and get (after factoring) [tex] (1+m ^{2}) * x^{2} + 4mx + 3 = 0[/tex]. Then you can plug this into the quadratic formula to get your x, but there I get stuck. i try to plug that back into y = mx +1 but I don't know what I am looking for.

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# Homework Help: Tangent lines to a circle

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