Calc problem

[Mathguy12345]

Suppose that f(t) is the cost to heat my house, in dollars per day, when the outside temp is T in Degree F. If f(29)=8.23 and f'(29)=-0.16, approximately what is the cost to heat my house when the outside temp is 26 degrees F?

 

[Deleted member 4993]

Suppose that f(t) is the cost to heat my house, in dollars per day, when the outside temp is T in Degree F. If f(29)=8.23 and f'(29)=-0.16, approximately what is the cost to heat my house when the outside temp is 26 degrees F?

Use approximation:

f(x_o+h) = f(x_o) + h*f'(x_o)

Please share your work with us, indicating exactly where you are stuck - so that we may know where to begin to help you.