Question

A certain region is losing 16 million acres of rain forest each year.
Find a linear function f that calculates the change of acres in the rain forest in millions in x years.
Find f(5) and interpret the result.

Answer 1

x(-1.6*10^7) = y

Answer 2

I made 1.6*10^7 negative because you are losing acreage

Answer 3

y = the total acreage of rainforest lost per year

Answer 4

so,

f(x) = x(-1.6*10^7)

Answer 5

now solve

f(5) by replacing x in the equation with 5

Answer 6

f(x) = x(-1.6*10^7)

at

f(0) = 0(-1.6*10^7) = 0

thus I dont see how your solution is any different from mine

Answer 7

yes

Answer 8

@sauravshakya
the only difference is, is I did not reduce the number to 16, which is probably the correct thing to do as it tells you to calculate in millions

Answer 9

so I guess we can agree that the solution is
f(x) = x(-16)

where the answer is in millions

Answer 10

Okay Thanks let me see if I can get the same answer

Answer 11

0*-16 = 0

that is how

Answer 12

yes but its asking for the change in acres per year not the total acres

Answer 13

we know that it changes by -16 million per year, thus the change is just the function

f(x) = -16x

Answer 14

Oh yes..........

Answer 15

it is ok I'm guilty of not fully reading or comprehending a question often on this site :)

Answer 16

I am having trouble with how much was lost per year. Is is 5 year and what rate?

Answer 17

f(5) just means you replace x with 5 in the equation

Answer 18

A point use to be

(x,y)
now it is
(x,f(x))

in your case you are looking for the point

(5,f(5))

Answer 19

So it would be over a five years? Than you no point is needed. I am workin gon the rate per year. Would it be 80 million a year

Answer 20

f(x), g(x), s(x)...

it is just new way of saying y, we use this notation for 2 reasons, it makes it easy to talk about multiple functions and 2 it allows us to talk about a specific point in a function easily that otherwise could be ugly in reality

Answer 21

-16*5 = f(5)

Answer 22

Okay thank you

Answer 23

f(5) = -16*5

thus you would lose 80 million acres

you have the point

(5, -80)

Answer 24

if you have any further questions ask