1)1. (3-7x)y+7y(x+9)=264
3y-7xy+7xy+63y=264
(-7xy+7xy)+(3y+63y)=264
66y=264
y=264÷66
y=4
2.x(4-y)=y(8-x)-34
4x-xy=8y-xy-34
4x-8y+(xy-xy)=34
4x+8y=34
4x+8×4=34
4x+32=34
4x=34-32
4x=2
x=2÷4
x=0.5
ответ:(0.5;4) ( или x=0.5;y=4)
1)1. (3-7x)y+7y(x+9)=264
3y-7xy+7xy+63y=264
(-7xy+7xy)+(3y+63y)=264
66y=264
y=264÷66
y=4
2.x(4-y)=y(8-x)-34
4x-xy=8y-xy-34
4x-8y+(xy-xy)=34
4x+8y=34
4x+8×4=34
4x+32=34
4x=34-32
4x=2
x=2÷4
x=0.5
ответ:(0.5;4) ( или x=0.5;y=4)