Question

0,2x+15y=9,8
0,75-10y=-3

Answer 1

$\left \{ {{0,2x+15y=9,8} \atop {0,75-10y=-3}} \right. \\ 0.75+3=10y \\ y= \frac{0.75+3}{10} \\ 0,2x+15(\frac{0.75+3}{10} )=9,8 \\ 2x+15(0.75+3)=98 \\ 2x+11.25+45=98 \\ 2x=41.75 \\ x=20,875 \\ 0.2*20.875+15y=9.8 \\ 15y=9.8-4.175 \\ 15y=5.625 \\ y=0.375 \\ \left \{ {{y=0.375} \atop {x=20,875}} \right.$
Ответ: y=0.375, x=20,875.