Question

Решите систему уравнений, СРОЧНО!!! 9x-10y=3 2x-3y=6

Answer 1

$\left \{ {{9x-10y=3} \atop {2x-3y=6}} \right. \ \ \left \{ {{9x-10y=3} \atop {2x=6+3y}} \right. \ \ \left \{ {{9x-10y=3} \atop {x= \frac{6+3y}{2} }} \right. \\ \\ 9* \frac{6+3y}{2}-10y=3\ |*2 \\ \\ 9(6+3y)-20y=6 \\ 54+27y-20y=6 \\ 7y=-48 \\y=- \frac{48}{7} =-6 \frac{6}{7} \\ \\ x= \frac{6+3y}{2} = \frac{6+3*(- \frac{48}{7}) }{2} = \frac{6- \frac{144}{7} }{2} =3- \frac{72}{7} = \frac{21-72}{7} =- \frac{51}{7} =-7 \frac{2}{7} \\ \\ OTBET:\ (-7 \frac{2}{7};-6 \frac{6}{7} )$