Odpowiedź:
a)
[tex]\left \{ {{x+y=2}/*(-1) \atop {x+y=9}} \right. \\\left \{ {{-x-y=-2} \atop {x+y=9}} \right.\\0=7 ,sprzecznosc[/tex]
c)
[tex]\left \{ {{2x-3y-7=0} \atop {-2x+1.5y-4=0}} \right. \\\left \{ {{2x-3y=7} \atop {-2x+1.5y=4}} \right.\\-1.5y=11\\y=- 7\frac{1}{3}\\2x-3*(-7\frac{1}{3})=7\\2x+22=7\\2x=-15 \\x=-7,5[/tex]
