Answer:
D: 8-4=4
Step-by-step explanation:
The earning of the salesperson is an illustration of a linear function.
The possible functions in the two scenarios are:
and 
The function is given as:

When the base salary is increased, a possible function is:

This is so, because 2500 is greater than 2000
When the commission rate is decreased, a possible function is:

This is so, because 0.05 is less than 0.1
So, the possible functions in the two scenarios are:
and 
See attachment for the graphs of both functions
Read more about linear equations at:
brainly.com/question/21981879
The simplified form would be -4×^2-13x+9
It’s 16 look at it a bit closer if you get confused step away and clear your mind a bit
first you put 12 over 100 and that is 12/100 and then simplify