A large company put out an advertisement in a magazine for a job opening. The first day the magazine was published the company got 90
responses, but the responses were declining by 10% each day.
Assuming the pattern continued, how many total responses would the
company get over the course of the first 19 days after the magazine was
published, to the nearest whole number?

C(19)=12 responses

Step-by-step explanation:

Exponential Decay Function

The exponential function is frequently used to model natural growing or decaying processes, where the change is proportional to the actual quantity.

An exponential decaying function can be expressed as follows:

Where:

C(t) is the actual value of the function at time t

Co is the initial value of C at t=0

r is the decaying rate, expressed in decimal

The company puts out an advertisement for a job opening. Initially, the company got 90 responses to the advertisement. Each day, the responses declined by 10%.

This is an example where the decay model can be used to calculate the responses to the advertisement at the day t.

The initial value is Co=90, the decaying rate is r=10% = 0.10. The model is written as:

Calculating:

We are required to calculate the number of responses at day t=19, thus:

C(19)=12 responses

x=30

step-by-step explanation:

the correct option is:

b. a value of the variable that makes the polynomial equal to zero.

the root or roots of a polynomial are the values of the variable that makes the polynomial equal to 0. we can find the roots of a polynomial making the expression equal to 0 and then, isolating the variable (it it has just one variable).

for example, given the following polynomial:

the root or zero of the polynomial, can be found by making the expression equal to 0, and then, isolating the variable, so, finding the root we have:

therefore, we have that the root of the polynomial is equal to 2.

we must remember that the number of roots that a polynomial can have, will depend on the degree of the polynomial, a first degree polynomial have will have one single root, a second degree polynomial (quadratic expression) may have two roots and so.

hence the correct option is:

b. a value of the variable that makes the polynomial equal to zero.

have a nice day!