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

If the line tangent to the graph of the function f at the point (1,7) passes through the point

(-2,-2), then f'(1) is?

Answer: 3

2. Relevant equations

3. The attempt at a solution

I got the right answer, but I think it was by pure luck. I found the slope using this formula:

y-y_{1}= m(x-x_{1})

Then I plugged everything in, getting:

7 + 2 = m(1 + 2)

9 = m3

m = 3

I originally created a new equation with this slope and (-2,-2) and did the derivative, but that's just rhetorical since the slope is 3 anyway. I guess I'm having a problem finding the equation of the derivative? Since once I have that equation, I can just plug in one. Or was my approach correct and the answer was y' = 3 (therefore no matter what point I plug in, the answer is 3 anyway)

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# Homework Help: What's f'(1) if the line tangent to the graph of the function at (1,7) passes (-2,-2)

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