Find the equations for the two tangent lines.

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Homework Statement


Find the equations for the two tangent line on the graph f(x) = - (x-3)^2 - 4 through the point (2,5)

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The Attempt at a Solution


I already solved for f '(x) which is -2x +6. Then I plug in 2 for f '(x) in order to find the slope, which is 2. Using the equation y - y1 = m(x -x1) I found the equation for my first tangent line to be y = 2x+1. My question is how do i find the second tangent line, and did I do something wrong?
 
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The point (2,5) is not on the curve y = f(x). Furthermore, the tangent line to f(x) at x=2 does not pass through the point (2,5). y=f(x) is a parabola, you need to consider the lines from points (x,f(x)) on the curve that pass through (2,5) and then solve for the lines whose slope matches f'(x).
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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