this is wrong cable.
this is TRS Male 1/8 to XLR - both sides are balanced
plus I'd rec a longer cable in any case
No, it won't be balanced. The audio out of his laptop is single ended.
The OP will need a 1/8th to RCA splitter. Then he will need an RCA to RCA splitter on one of the channels. Then he will need an RCA to TRS or RCA to XLR to the M-Audio and an RCA to RCA for the sub and another RCA to TRS or XLR to the other monitor.
In professional circles it if technically referred to as a 'kludge'
The other item of note that the OP has to take into consideration is if the input on the speakers will have enough sensitivity to be driven adequately with a consumer level device.
What I would do if I was the poster is hop on Craigslist and search for:
M-Audio, EMU, Presonus, Focusrite, Cakewalk, RME, Lynx, Roland, Tascam and find a pro-audio USB interface. If unsure about what you have found on C-List post it back here.
As example there is a
Cakewalk Sonar USB sound device for $75 on Craiglist near me. They even have Win 7 32/64bit drivers.