An airplace passes over an airport at noon traveling 300 mph due west.
At 1:00 Pm another plane passes over the same airport at the same elevation traveling de north at 350 mph.
Assuming both planes maintain their (equal) elevations, how fast is the distance between them changing at 2:30 pm?

Where do I start from here?

plot their positions and graph

At 1:oo one will be 300 miles west of center. At 2:00 one will be 600 miles west and 350 miles north. At 2:30 one will be 750 miles west and the other425 miles north.

Use any number of point of calculation to establish positional means, triangulate position to determine distance from each other.

Seems the way I would do it, but I never took calc.

Guess I'm not sure what to do once I get to that point.

That makes a Triangle, 750 West, 425 North but what do I do next?

525 north (350 x 1.5)

since it's a right triangle the distance between the planes is easy to calculate, namely sqrt(WxW + NxN) using W and N for the airplane positions
you could now as 'Papa_Kurr' suggested calculate the distance at 2:29 and 2:31 as well and go from there
not sure what you can use in calc 1, so i leave it at that

most likely you're on optimization or so, derivatives

cc=aa+bb

c= distance, find max/min etc by taking derivative

Derivative of what tho?
I have these numbers but nothing of an equation to derive :/ Lol?



Totally missed this quote.

This post was edited by Trev on Jun 30 2013 10:15pm

The answer I believe is -114.34 mph. However, it could also be 720.27mph, I'm not sure which one is correct.

Because it's going west does that make x negative? (If it make's x negative, that means it's -114.34mph) (This is for a slightly different equation, numbers are 500West @ 2.5 Hours and 550 North @ 1.5 hours)

nope, the distance is a fix measure (ie positive) regardless where the direction vectors point to
btw, can't be greater 650 mph (which would be the maximum possible if they would be traveling in opposite directions
and it has to be greater than 50mph (which would be the minimum possible if they would be traveling in the same direction

derivative of CC=AA+BB
plug in c,a,b, and respective da/dt , db/dt, to find dc/dt
you sure you're not going over this in class?
C= distance between 2 points

This post was edited by saber_x3 on Jul 1 2013 05:08am

This is a related rates problem. If you still don't understand i can explain and give you the answer for fg. lemme know