What is the formula for the tangent line of f(x)=−4x2+10x at x=−3?

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Lesson Parent: 
The Formula of the Tangent Line
Problem: 

What is the formula for the tangent line of f(x)=−4x2+10x at x=−3?

Answer: 

y=34x+36

SAMPLE SOLUTION

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Solution: 

We know that the general formula for the tangent line at a point xo for f(x) is

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In this problem <Sign in to see all the formulas> and <Sign in to see all the formulas> because f(x) is a polynomial and we know the derivative of a polynomial. Therefore,

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