# Homework Help: Problem solving with linear functions 2.

1. Sep 11, 2011

### davie08

1. The problem statement, all variables and given/known data

Suppose the selling price p of a product is linearly related to the quantity demanded q. If p=$15 when q=25, and p=$10 when q=100, and if q is at least 20 but not more than 150, find p as a function of q.

2. Relevant equations

3. The attempt at a solution

I couldn't find a sample problem for this so I would just guess that the domain would be
20<q<150.

2. Sep 11, 2011

### eumyang

If you were given two points, could you come up with a linear equation in slope-intercept form? If you can, then you should be able to do answer your question.