Question

A lawn care company charges a $20 tip fee plus $.25 per square foot of x square feet of lawn for fertilization. Write an equation that represents the relationship.

Answer 1

.25 is the slope in this equation. It shows the cost per square foot, and x represents the amount of square feet. 

20 is the constant. It will always be there, even if the lawn has no square feet or 3000. 

So, your equation should be $f(x) = \frac{1}{4}x+20$.

Answer 2

The constant in this situation is 20 and the rate of change is .25 ft, x. Therefore the equation is y=.25x+20