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

The teacher proposed a problem today during a math session. He gave the function : f(x) = x^{2}-6x+5 - and a point P(4,-6).

Our mission was to find two tangents for the given point. I thought it was easy, just differentiate the function, and insert the differentiate function for a in : y=a*x + b.

2. Relevant equations

function : f(x) = x^{2}-6x+5

differentiate : f'(x) = 2x-6

tangent: y= (2x-6)*x + b

tangent eq: -6= (2x-6)*4 + b

3. The attempt at a solution

Given the last tangent equation, my plan was to find the two b's, where the tangents met the y-axis. But I failed.

Any thoughts?

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# Homework Help: Two tangents with same (X,Y)

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