Simple questions on the TI89 Titanium

[pondwire]

Hello. I'm just learning my new TI89 Titanium and found an online tutorial. One of the example problems, however, doesn't produce the same answer or equivalent on my calculator. Can anyone offer any ideas why this may be? Here's the example:
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Suppose we want to solve the following system of equations:
2x-3y+5z=-1
-3x+5y-2z=3
5x-7y+8z=-2

solve(2x+3y+5z=-1 and -3x+5y-2z=3 and 5x-7y+8z=-2,{x,y,z})
or
zeros({2x+3y+5z+1 ,-3x+5y-2z-3 ,5x-7y+8z+2},{x,y,z})

ans: x=21/10 and y=19/10 an>
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The answer I get is [ -141/74 -19/74 53/74]
Also, in the example above, "and" is used in solve command. Does anyone know where this button is found? Thanks a lot, I really need the help...