How Is Energy Conserved in a Photon-Electron Collision?

[Phoenixtears]

Homework Statement

An incident photon having a frequency of 2.00 E10^19 Hz collides with an electron initially at rest.

What is the total energy of the two-particle system after the collision? (In joules

The Attempt at a Solution

I've stared at this problem for at least an hour an have no idea where to go from here. Can anyone give me a leg up on this one. It feels like there isn't enough given information to even begin this... no velocity, no wavelength.

Thanks in advance!

~Phoenix

 

[whybother]

Well, to be fair... it's a photon, so you know the velocity (ie. the speed of light), and since you have the frequency, you have the wavelength - perhaps you can see it from there?