[latex]left{ {{frac{1}{2}x+frac{1}{4}y=0,25} atop {-frac{3}{4}x-frac{1}{2}y=0,5}}
ight.[/latex]
drugie równanie mnożymy przez 1/2 obustronnie
[latex]left{ {{frac{1}{2}x+frac{1}{4}y=0,25} atop {-frac{3}{8}x-frac{1}{4}y=0,25}}
ight.[/latex]
dodajemy równania stronami
[latex]frac{1}{2}x-frac{3}{8}x=0,25+0,25[/latex]
[latex]frac{4}{8}x-frac{3}{8}x=0,5[/latex]
[latex]frac{1}{8}x=frac{1}{2}[/latex]
[latex]x=frac{1}{2} cdot 8[/latex]
[latex]x=4[/latex]
[latex]frac{1}{2} cdot 4+frac{1}{4}y=frac{1}{4}[/latex]
[latex]2+frac{1}{4}y=frac{1}{4}[/latex]
[latex]frac{1}{4}y=-frac{7}{4}[/latex]
[latex]y=-7[/latex]
odp. [latex]left{ {{x=4} atop {y=-7}}
ight.[/latex]