Answer:
[tex]y(x)=100+0.1x[/tex]
Step-by-step explanation:
Let y represent the total fee (in dollars) of a trip where they climbed x vertical meters.
We know that there is an initial fee of $100, so we know that if we climb x=0 meters, we have a fee of y(0)=100.
[tex]y(0)=100[/tex]
As there is a constant fee (lets called it m) for each vertical meter climbed, we have a linear relationship as:
[tex]y(x)-y(0)=m(x-0)\\\\\\y(x)-100=mx\\\\\\y(x)=100+mx[/tex]
We know that for x=3000, we have a fee of $400, so if we replace this in the linear equation, we have:
[tex]y(3000)=100+m(3000)=400\\\\\\100+3000m=400\\\\3000m=400-100=300\\\\m=300/3000=0.1[/tex]
Then, we have the equation for the total fee in function of the vertical distance:
[tex]y(x)=100+0.1x[/tex]