Question

The cost of creating a software program is $5000. Every extra feature added to the software costs $100. Thetotal charge of the software with x extra features is given by the function f(x) = 100x + 5000. How will the graphof this function change if the basic cost is raised to $5200 and the cost of each extra feature is increased to$120?

Answer 1

The original function is:

`f(x)=100x+5000`

Which means that it has a slope of 100, and a starting point of 5000.

As we can see on the image above, the first point is (0,5000), which is the starting point of the function. The second point is (2, 5200), which means that for a 2 unit increase on the features, we got 200 increase on the price, leading to a slope of 100.

If we change the basic cost to 5200, the starting point of the function will increase by 200 units, if we change the slope to 120, then for every feature we add, the cost will increase faster. In summary, the cost of the program will be higher to start, and it will also increase faster. This is illustrated in the image below:

`g(x)=120x+5200`

In green we have the new function, and in red we have the old one. We can see that the new one increases faster, and is always above the old one.