Is my answer correct?
write an exponential function to model this situation: a population of 420 animals decreases at an annual rate of 21%. then predict the value of the function after 5 years (to the nearest whole number).

The value of the function after 5 years would be 129.

Step-by-step explanation:

We have been that a population of 420 animals decreases at an annual rate of 21%. We are asked to write an exponential function for our given problem.

We know that an exponential function is in form , where,

a = Initial value,

b = For decay b is in form , where, r represents decay rate in decimal form.

Therefore, our required function would be .

To find the value of the function after 5 years, we will substitute in our function.

Therefore, the value of the function after 5 years would be 129.

the answer would be c:   ax + b = ax + c

step-by-step explanation:

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4