SOLUTION: The distance from city A to city B is approx. 2160 miles. A plane flying directly to city B passes over A at noon. If the plane travels at 500 mph, find the rule of the function f(

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Question 1092503: The distance from city A to city B is approx. 2160 miles. A plane flying directly to city B passes over A at noon. If the plane travels at 500 mph, find the rule of the function f(t) that gives the distance of the plane from city B at time t hours (with t=0 corresponding to noon)
f(t)=?
Answer by greenestamps(13200) (Show Source):
You can put this solution on YOUR website!

The plane is flying at a constant rate, so the function will be linear, of the form

or

In that equation, b is the y-intercept (f(0) -- the distance of the plane from B at t=0, when it flies over A.) And m is the slope (rate of change; i.e., how fast the distance from B is changing -- i.e., the speed of the plane).

So b is 2160 (when the plane flies over A, it is 2160 miles from B), and m is -500 (the distance of the plane from B is decreasing at the rate of 500 miles each hour).

And so the function is