Question

For `f(x) =(5+4x)^2`, what is the equation of the line tangent to `x =7`?

Answer 1

First find the slope at `x=7`, then use the point slope format to find the tangent line.

Explanation:

`f(x)'=8(5+4x)`

`f'(7)=264`

`f(7)=1089`

`(y-y_1)=m(x-x_1)`
`(y-1089)=264(x-7)`

Tangent Line : `y=264x-759`

hope that helped