Functions

[Tmealy]

A certain region is losing about 28 million acres of rain forest each year:

Find a linear equation function that calculates the change in acres of rain forest in millions x years

f(x)=

simplify f(5)

After how many years, the the region can expect to lose about how many million acres of rain forest?

so far I have: f(x)= 28²
40+x²

f(5)= 28(5)²
40+(5)²

= 700
65

=10.8 After 5 years, the region can expect to have lost about 10.7 million acres of rain. Is this the correct way to solve this problem?

 

[JeffM]

A certain region is losing about 28 million acres of rain forest each year:

Find a linear equation function that calculates the change in acres of rain forest in millions x years

f(x)=

simplify f(5)

After how many years, the the region can expect to lose about how many million acres of rain forest?

so far I have: f(x)= 28²
40+x²

f(5)= 28(5)²
40+(5)²

= 700
65

=10.8 After 5 years, the region can expect to have lost about 10.7 million acres of rain. Is this the correct way to solve this problem?

You need to apply a little common sense. If the region is losing 28 million acres EACH year, how in the world can it lose only 10.8 million in five years? You are told to develop a linear function: Is

\(\displaystyle f(x) = \dfrac{28x^2}{40 + x^2}\) linear?

How muh will be lost in 1 year?

How about 2?

How about 3?

Do you see a pattern on which to base a linear function?