Question

Fan and Medal

The change in water level of one portion of the mississippi River is about -0.3 ft per day. If the water level starts at 17 feet and falls for x days, the level represented by the function f(x) = 17 - 0.3x

a. Find the intercepts and graph the function
b. What does each intercept represent

Answer 1

please if I set x=0 into the formula for f(x), what do you get?

Answer 2

What?

Answer 3

please what is f(0), namely what is 17-0.3*0=?

Answer 4

It Equals 17

Answer 5

ok! y=17 is your y-intercept

Answer 6

Now, please if I set f(x)=0, I have thisequation below:
-0.3*x+17=0
please compute x

Answer 7

I dont get what your trying to say

Answer 8

please solve this equation:
-0.3*x+17=0

Answer 9

x=56.666667

Answer 10

that's right! So x=56.67 (approximated value) or x=170/3 is your x-intercept

Answer 11

And how do i Graph that

Answer 12

it is vey simple, since your line has to pass at point (0,17) and it has to pass at point (56.67,0)

Answer 13

oops..it is very simple...

Answer 14

Its okay. So if im right the bottom half gets shaded in?

Answer 15

no, I don't think, because your line represents the function f(x), of course you have to consider positive values of x only, and positive values of f(x) only