Question

решите пж
система уровнений
1){3х-у=9,
{5х+у=7;
2){2х+5у=5,
{4х+3у=15;

Answer 1

готово. Учись на отлично

Answer 2

1){3х-у=9,
{5х+у=7;
3x-y+5x+y=9+7
8x=16|:8
x=2
5*2+y=7
y=7-10
y=-3
(2;-3)
2){2х+5у=5|*(-4)
{4х+3у=15|*2
{-8x-20y=-20
{8x+6y=30
-8x-20y+8x+6y=-20+30
-14y=10|:(-14)
y=-(10/14)
y=-5/7
2x+5*(-5/7)=5|*7
14x-25=35
14x=35+25
14x=60|:14
x=60/14
x=30/7=4(2/7)
(4(2/7); (-5/7))





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