Posted by **art** on Friday, February 11, 2011 at 11:02pm.

f(x)=3-5x , (-1,8) find the slope of the tangent line to the graph of the function at the given point

how do you figure this out?

- calculus -
**Reiny**, Friday, February 11, 2011 at 11:07pm
since your function is a straight line

and it is in the form f(x) = mx + b

the slope anywhere on the line is -5

no work needed here.

- calculus -
**Allison**, Friday, February 11, 2011 at 11:09pm
To find the slope of the tangent line you have to take the first derivative of f(x). So f'(x)=-5. Or you can also see that from the formula y=mx+b, where m is slope and b is your y intercept, that -5 is the slope. Because the original function is a line, the slope is the same at every point.

- calculus -
**helper**, Friday, February 11, 2011 at 11:10pm
To find the slope of the tangent line at a point means to find the derivative of f(x).

f(x) = 3 - 5x

f' = 0 - 5

f' = -5

Then, normally, you would plug in the given point, (-1, 8), to find the slope.

But since f' = 5 with no variable x, for instance, there is nowhere to plug in the point.

Therefore, the slope is everywhere.

## Answer this Question

## Related Questions

- calculus - 1. Which of the following expressions is the definition of the ...
- Calculus: for mathmate - Find the slope of the tangent line to the graph of the ...
- Calculus - Find the slope of the functions graph at a given point. Then find an ...
- Calculus - Find the slope m of the tangent line to the graph of the function at ...
- Calculus - Find the slope m of the tangent line to the graph of the function at ...
- Calculus PLEASE HELP - Find the slope m of the tangent line to the graph of the ...
- Calculus - Find the slope m of the tangent line to the graph of the function at ...
- calculus - Use the four-step process to find the slope of the tangent line to ...
- calculus - find the point on the graph of the given function at which the slope ...
- Calculus - Use the four-step process to find the slope of the tangent line to ...