Help me, please! It's due tomorrow!

m=y2-y1 / x2-x1

m=15-20 / 1-0

m=-5 / 1

m=-5

y=mx+b

20=-5*0+b

20=0+b

20=b

y=-5x+20

The population of bacteria can be expressed as a function of number of days.

Population = where n is the number of days since the beginning.

Step-by-step explanation:

Number of bacteria on the first day=

Number of bacteria on the second day =

Number of bacteria on the third day =

Number of bacteria on the fourth day =

As we can see , the number of bacteria on any given day is a function of the number of days n.

This expression can be expressed generally as where n is the number of days since the beginning.