1)4х + 3у =5и х-у =3 2) х-у =7 и 5х -3у =1 3) - вопрос №55746011435327531365622 от braagin 06.04.2020 02:51

Question

Математика: 1)4х + 3у =5и х-у =3 2) х-у =7 и 5х -3у =1 3) 6х +5у =6 и 2х +у =-2

braagin · Answer

4x+3y=5 4(y+3) + 3y=5 4y+12+3y=5 7y=-7 y=-1
x-y=3 x=y+3 x=y+3 x=y+3 x=-1+3= 2

x-y=7 x=y+7 x=y+7 x=y+7 x=y+7 x=-17+7=-10
5x-3y=1 5(y+7)-3y=1 5y+35-3y=1 2y=-34 y=-17 y=-17

6x+5y=6 6x+5y=6 6x+ 5(-2x-2)=6 6x-10x-10=6 -4x=16 x=-4
2x+y=-2 y=-2x-2 y=-2x-2 y=-2x-2 y=-2x-2 y=-2*-4-2=6