Answer: The consultant earn $50 each hour.
Explanation:
It is given that for 4 hours of work, the consultant charges $400. For 5 hours of work, she charges $450. The amount that a consultant charges for her work can be modeled using a linear function.
If the linear function represents the amount earn by consultant in hours the the coordinates can be written as (4, 400) and (5, 450).
If we want to find how much money does the consultant earn each hour, so first we have to find the slope of linear function which passing through two points (4, 400) and (5, 450).
In the linear function the slope show the earning of consultant per hour, therefore consultant earn $50 each hour.