With 49/50 you can solve this systems in 2 ways :

1/Use LINSOLVE with vectors

['X+Y=30' 'Y=Z+2' 'X=14+Z'] @ you can use Matrix and equation writer for this

[ 'X' 'Y' 'Z' ] @ It must be _vectors_ and not matrices ( VEC must be check in matrix writer : VEC#)

LINSOLVE @ Shift S.SLV LINSO

->

[ X=21 Y=9 Z=7 ]

This works in symbolic way even with more than 3 unknows for 3 equations

I have forgot that this don't work on 48

|x| |x| -1

2/ Use matrices : M.|y|=V => |y| = M .V

|z| |z|

[[1 1 0] @ With matrix writer type

[0 1 -1] @ 1 1 0 ENTER RShift <- v

[1 0 -1]] @ 0 1 -1 1 0 -1 ENTER

[[30][2][14]] @ With matrix writer 30 ENTER 2 14 ENTER

@ or [] [] 30 -> 2 14 ENTER

SWAP /

->

| 21 |

| 9 |

| 7 |

This works in numeric and symbolic with HP49/50

Only in numeric with my old 48SX (it works here for exemple)

*Edited: 16 Apr 2012, 5:12 p.m. *