Question

A population of mold decays at a rate of 25 mold spores per day. Assume that the initial population of mold spores is 1640 spores.Step 1 of 2 : Write a function to model the decay rate of the mold spores based on the number of days that have passed. Use x for the independent variable.

Answer 1

Since the decay rate is constant for each day we can consider it as a slope and represent it as a linear function that fits the population decay.

$y=mx+b$

since it is a decay we know that the slope is going to be negative and b is going to be the initial population.

$y=-25x+1640$