posted by spencer on .
use the phythagorean theroem to answer this question. becca paddles a boat from the south bank of a stream to the north bank. She paddles at a rate of 8 mph. The stream is flowing west at a rate of 6 mph. what is beccá actual velocity. I need to understand how to figure this quesiton out.
she is going north at 8
she is going west at 6
Draw a vector north (up) 8 units long.
At the tip of that, the north end, draw a vector west(left) 6 units long.
Add those two vectors by drawing the hypotenuse from lower right to upper left.
Find the length of that hypotenuse.
That is the magnitude of your resultant velocity.
The angle the hypotenuse makes with the north vector at its base is the angle west of north of the resultant vector. Its tangent is 6/8 or 3/4