Thread: Vector application problem

Hello! I am having trouble on this problem, any help would be really appreciated!

"Felicia and Joseph paddle a canoe across a river at a speed of 7 mph. The river's current is flowing at 3 mph. Find the actual speed of the canoe and the angle x between the canoe's heading and its course."

That's the problem and here's the picture that came with it. (I had to redraw the diagram but it's pretty much similar, sorry if it's funky and not proportion)



Please and thank you!

Edit: Um never mind!! Thank you for all your help though! I tried it again and found the answer through Pythagorean theorem and law of cosine. But if anyone would like to check my answer, the speed I got was root 58 and x is 23 degrees.

Originally Posted by wanderlust

Hello! I am having trouble on this problem, any help would be really appreciated!

"Felicia and Joseph paddle a canoe across a river at a speed of 7 mph. The river's current is flowing at 3 mph. Find the actual speed of the canoe and the angle x between the canoe's heading and its course."

That's the problem and here's the picture that came with it. (I had to redraw the diagram but it's pretty much similar, sorry if it's funky and not proportion)



Please and thank you!

Edit: Um never mind!! Thank you for all your help though! I tried it again and found the answer through Pythagorean theorem and law of cosine. But if anyone would like to check my answer, the speed I got was root 58 and x is 23 degrees.

Hi wanderlust,

Looks pretty good to me, but you didn't need to use the law of cosine. The new course across the river is the diagonal of a rectangle. Just find arctan of 3/7 to get the angle.