MANUAL FOR INSTRUCTORS

The two lines in the row picture are the same line, containing all solutions. 6 Singular system if b = 4, because 4 x+8 yis 2 times 2 +4 . Then g = 32 makes the lines 2x+4y = 16 and 4x+8y = 32 becomethe same: infinitely many solutions like (8,0) and (0,4). 7 If a = 2 elimination must fail (two parallel lines in the row picture). The equations ................
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