Odpowiedź:
a)
[tex]\left \{ {{y=-7+2x} \atop {-3x+4y=-3}} \right. \\\\-3x+4(-7+2x)=-3\\x=5 \\y=3[/tex]
b)
[tex]\left \{ {{x+2y=9} \atop {-3x-2y=-11}} \right. \\\left \{ {{2y=9-x} \atop {-3x-2y=-11}} \right. \\-3x-(9-x)=-11\\x=1\\-3*1-2y=-11\\y=4[/tex]
itd.