Помогите решить систему уравнений
{8x+3y=-7 {5x-y=10 {8x+3y=-7 {y=5x-10 {8x+3(5x-10)=-7 {y=5x-10 {8x+15x-30=-7 {y=5x-10 {23x=-7+30 {y=5x-10 {23x=23 {y=5x-10 {x=1 {y=-5