Помогите пж до 13:00
Ответы
Ответ:
Объяснение:
номер 3
(6х+у=10
(6x-3y= -26
6х+у=10
6х=10-y
(6х=10-y
(6x-3y= -26
10-y03y= -26
y=9
6x-3*9= -26
x=1/6
номер 4
(8x+3y=1
(2x-4y= -18
8x=1-3y
x=1/8-3/8у
(x=1/8-3/8у
(2x-4y= -18
2(1/8-3/8у)-4y= -18
1/4-3/4у-4y= -18
1/4-19/4у= -18
1-19y= -72
-19y= -73
y= 73/19
x=1/8-3/8*73/19
x=1/8-219/152
х= -25/19
(х,у)=(-25/19, 73/19)
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номер 5
(5x-3y=13
(2x-4y=3
5x=13+3y
x=13/5+3/5у
(x=13/5+3/5у
(2x-4y=3
2(13/5+3/5у)-4y=3
26/5+6/5у-4у=3
26/5-14/5у=3
26-14у=15
-14у=15-26
-14у= -11
у=11/14
х=13/5+3/5*11/14
х=13/5+33/70
х=43/14
(х,у)=(43/14, 11/14)
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номер 6
(4х-5у=2
(6х-7у= -11
4х-5у=2
4х=2+5у
х=1/2+5/4у
(х=1/2+5/4у
(6х-7у= -11
6(1/2+5/4у)-7у= -11
3+15/2у-7у= -11
3+1/2у= -11
6+у= -22
у= -22-6
у= -28
х=1/2+5/4* (-28)
х=1/2-5*7
1/2-35
х= -69/2
(х,у)=(-69/2, -28)