3х+у=1 2х-5у=-22 5х+у=24 7х+4у=18 помогите пожалуйста

1) $\left \{ {{3x+y=1} \atop {2x-5y=22}} \right.$
$\left \{ {{y=1-3x} \atop {2x-5(1-3x)=22}} \right.$
$\left \{ {{y=1-3x} \atop {2x-5+15x=22}} \right.$
$\left \{ {{y=1-3x} \atop {17x-5=22}} \right.$
$\left \{ {{y=1-3x} \atop {17x=27}} \right.$
$\left \{ {{y=1-3x} \atop {x= \frac{27}{17}}} \right.$
$\left \{ {{y=1-3\frac{27}{17} } \atop {x= \frac{27}{17}}} \right.$
$\left \{ {{y=-3\frac{10}{17} } \atop {x= \frac{27}{17}}} \right.$

2) $\left \{ {{5x+y=24} \atop {7x+4y=18}} \right.$
$\left \{ {{y=24-5x} \atop {7x+4(24-5x)=18}} \right.$
$\left \{ {{y=24-5x} \atop {7x+96-20x)=18}} \right.$
$\left \{ {{y=24-5x} \atop {-13x=-78}} \right.$
$\left \{ {{y=24-5x} \atop {x=5}} \right.$
- $\left \{ {{y=24-5*6} \atop {x=6}} \right.$
$\left \{ {{y=-6} \atop {x=6}} \right.$