Thank you for making this textbook available. Hope this is the appropriate method to make this comment.
There might be a typo in the example in section 1.2.1.
"Substituting for y and z in the first equation gives
x + 2 ·(−2) + 3·3 = 6, or x = 3. Thus the only solution is (x, y, z) = (1,-2, 3)."
Thank you for making this textbook available. Hope this is the appropriate method to make this comment.
There might be a typo in the example in section 1.2.1. "Substituting for y and z in the first equation gives x + 2 ·(−2) + 3·3 = 6, or x = 3. Thus the only solution is (x, y, z) = (1,-2, 3)."
Possibly "x=3" should be "x=1".