Сложим
2х+15х-3у+3у=7+10
17х=17
х=1
2×1-3у=7
2-3у=7
-3у=7-2
-3у=5
у=-5/3=-1 2/3
(1; -1 2/3)
1) 2х-3у-11х+8у=5у-9х,
2) 5(2а+1)-3=10а+5-3=10а+2,
3) 14х-2(х-1)+(2х+6)=14х-2х+2+2х+6=14х+8.
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1) (x-y)+y=-3+2x
x=-3+2x
x=3
y=2*3=6
2) (2x-y)+y=-4+3x
2x=-4+3x
x=4
y=3*4=12