Question

решите системное уравнение 3x+2y=8
4x-y=7

Answer 1

$\left \{ {{3x+2y=8} \atop {4x-y=7}} \right. \\ y=4x-7 \\ \\ 3x+2(4x-7)=8 \\ 3x+8x-14=8 \\ 11x=22 \\ x=22:11 \\ x=2 \\ \\ 4*2-y=7 \\ 8-7=y \\ y=1$

Answer 2

{2у=8-3х /:2 { у=4-1,5х
4х-у=7 4х-(4-1,5х)=7

{у=4-1,5х {у=4-1,5х
4х-4+1,5х=7 4х+1,5х=7+4

{у=4-1,5х {у=4-1,5х
5,5х=11 х=2

{у=4-1,5*3 {у=-0,5
х=2 х=2