Question

Ajutor e urgent va rog!!! ​

Answer 1

Răspuns:

Explicație pas cu pas:

3x+4y= 10l*2

2x-2y=  2  l* -3

-

6x+8y=20

-6x+6y= -6

/    14y= 14

y= 14/14

y= 1

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2x-2*1= 2

2x-2=2

2x=2+2

2x=4

x=4/2

x= 2

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S= {2,1}

-

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b)

7x-2y=18 l *9

9x-7y=32 l* -7

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63x-18y= 162

-63x+49y=- 224

  /   31y=-62

y= -62/31

y= -2

-

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9x-7*(-2) =32

9x+14=32

9x= 32-14

9x= 18

x= 18/9

x= 2

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S= { 2,-2}