related rates problem help

[mey3024]

a week ago you were on duty in an helicopter, hovering 1000 feet above route 5, when a car zipped by at high speed. the radar reported that at the moment the car was a 2000 feet from your helicopter and moving away from you at a rate of 90 feet per sec.You radioed ahead to your partner on the ground and had him stop the car and issue a speeding ticket. today the car's driver appeared in court. she tells the judge that she was clocked at 90 ft/sec. the speed limit was 65mph, which work out to a little over 95 ft/sec. she said that she wasn't speeding at all. show the judge how fast she was going

 

[Deleted member 4993]

a week ago you were on duty in an helicopter, hovering 1000 feet above route 5, when a car zipped by at high speed. the radar reported that at the moment the car was a 2000 feet from your helicopter and moving away from you at a rate of 90 feet per sec.You radioed ahead to your partner on the ground and had him stop the car and issue a speeding ticket. today the car's driver appeared in court. she tells the judge that she was clocked at 90 ft/sec. the speed limit was 65mph, which work out to a little over 95 ft/sec. she said that she wasn't speeding at all. show the judge how fast she was going

Draw a sketch.

Use Pythagorus

Differentiate...

Please share your work with us so that we may know where to begin to help you.

 

[renegade05]

Here's a start

\(\displaystyle h = hypotenuse\)
\(\displaystyle x = adjacent\)
\(\displaystyle o = opposite = 1000ft\) (CONSTANT)
\(\displaystyle \frac{dh}{dt}= 90 ft/sec\)
\(\displaystyle \frac{dx}{dt} = ???\)
when h = 2000ft

Hmm.. I just noticed Subhotosh Khan already posted a reply to this.. well maybe this will help regardless.