A marathon runner is running across a bridge. She has 10,000 J of kinetic energy, and she has 20,000) of potential energy because she is on the bridge (above the ground). What is her mechanical energy?
30,000
10.000
20,000
15,000

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west

i'm on my way to history not a mistory.