# Angles totally mess me up

## Homework Statement

Two 75.0 kg hockey players skating at 5.90 m/s collide and stick together. If the angle between their initial directions was 135°, what is their speed after the collision? (Let the motion of player 1 be in the positive x-direction and the motion of player 2 be at an angle of 135° measured counterclockwise from the positive x-axis.)

also the answer is to be the velocity in the x direction, and the velocity in the y direction

## Homework Equations

I've tried a bunch relating to momentum..

## The Attempt at a Solution

I tried using trig, but there must be and easier way that I'm missing

ONE MORE:
The collision between a hammer and a nail can be considered to be approximately elastic. Estimate the kinetic energy acquired by a 11 g nail when it is struck by a 550 g hammer moving with an initial speed of 4.9 m/s.

I know that KE = .5mv^2 and that this is elastic, therefore the initial KE must equal the final KE. I got 2.4, which seems close, but still incorrect.

Related Introductory Physics Homework Help News on Phys.org
For the hockey question, do use trig. Break the velocities for both players into vertical and horizontal components.

For the player going in the x-direction: p_x = mv

For the other player: p_x = -mvcos45 and p_y = mvsin45

Also, remember that momentum is conserved for both the horizontal and vertical directions. Vertically,

mvsin45 = (m+m)v_after.

Do the same for the horizontal component. I've probably done too much as it is.