Word Problem....I don't know what to do

[snow123]

Hi,
I don't know how to solve this word problem:
A rock dropped into a pond sends out a circular ripple whose radius increases steadily at 6cm per second. A toy boat is floating on the pond 2m east and 1m north of the spot where the rock is dropped. How long does it take for the ripple to reach the boat?
I don't know what to do first. Please help me.

 

[tkhunny]

I would give the Pythagorean Theorem some serious thought. Just how far from the drop zone is the boat?

 

[soroban]

Then be careful . . .

The ripple is moving at 6 centimeters per second.

The distance is measured in meters . . . sneaky!

 

[snow123]

Thank you....but, I still don't get it.
what numbers would I use for the Pythagorean Theorem?

 

[Denis]

R = point where Rock fell

From R, go 2m (200 cm) horizontally (East of R) ; then go up 1m (100 cm) vertically (North).
(So you are now at the Boat's location)
Do you "see" the right triangle now?

 

[snow123]

Thank so much!
I figured it out!

 

[Johnnyq]

Great solution. There are always tricks with Pythagorean theorem. The site below has a good explanation of the theorem..


[spamming url edited out - SK]

 

[mmm4444bot]

Great solution.

Where?


There are always tricks with Pythagorean theorem. The site below has a good explanation of the theorem.

I'm more interested in a good explanation of the tricks which you claim are always present.