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

Let f(x)= a (7-x^2) for all a does not equal 0

a) Find, in terms of a, the equations of the lines tangent to these curves at x=-1

b) Find, in terms of a, the y-intercepts of the tangent lines at x=-1

c) find the x-intercepts of the tangent lines at x=-1

d)find, in terms of a, the area enclosed by the graph of f(x), the tangent line at x=-1, and the y-axis

2. Relevant equations

None? How to find a derivative?

3. The attempt at a solution

So I finished part a and i got y=2ax +8a

I got the derivative (-2ax) which was also the slope then i just plugged -1 into the original equation and I got 6a. Using the point slope equation, i got y = 2ax +8a, which i know is right. I don't understand b,c, or d so any help would be great! Thanks :)

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# Homework Help: Finding tangent lines, y-intercepts, x-intercepts, etc. with a given equation

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