Помогите решить систему уравнения 1) 3x+8y=13 5x-16y=7 2) 10x+15y=-45 2x-3y=33

№1.
$\left \{ {{3x+8y=13/*2} \atop {5x-16y=7}} \right. \\ + \left \{ {{6x+16y=26} \atop {5x-16y=7}} \right. \\11x=33\\x=3\\5*3-16y=7\\-16y=7-15\\-16y=-8\\y=1/2$
№2.
$\left \{ {{10x+15y=-45} \atop {2x-3y=33}} \right. \\\\ \left \{ {{x= \frac{33+3y}{2} } \atop {10*( \frac{33+3y}{2} )+15y=-45}} \right. \\ \\165+15y+15y=-45\\30y=-210\\y=-7\\x= \frac{33+3*(-7)}{2} =6$