Question

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1) -x-y = 2 2) -2(5x-2y)+4(2x+y) = 1

2(3x+y) = -20 3(2x-y)-(y+7x)=5,5

Answer 1

1)-x-y=2/*2                      2)-10x+4y+8x+4y=1

6x+2y=-20                           6x-3y-y-7x=5,5

-2x-2y=-4                            -2x+8y=1

6x+2y=-20                            -x-4y=5,5/*(-2)

4x=-24/:4                             -2x+8y=1

-x-y=2                                    2x+4y=-11

x=-6                                     12y=-10/:12

-6-y=2                                   -x-4y=5,5

x=-6                                      y=-10/12

-y=2+6                                   -x-4*(-10/12)=5,5

x=-6                                      y=-10/12

-y=8/*(-1)                             -x+30=5,5

x=-6                                      y-10/12

y=-8                                      -x=-24,5/*(-1)

y=-10/12

 

x=24,5

 

 

 

 

 

Answer 2

1)-x-y = 2                                   2)-2(5x-2y)+4(2x+y) = 1

2(3x+y) = -20                                3(2x-y)-(y+7x)=5,5

 

-x-y=2                                             -10x+4y+8x+4y=1

6x+2y=-20                                         6x-3y-y-7x=5,5

 

-x=2+y                                              -2x+8y=1

6(2+y)+2y=-20                                      -x-4y=5,5/(razy)-2

 

-x=2+y                                                                                                         12+6y+2y=-20                                     -2x+8y=1

 

-x=2+y                                               2x+8y= -11

6y+2y=-20-12

 

-x=2+y                                               16y=-10/16

8y=-32/8                                         y=-10/16

 

-x=2+y                                             -2x+8(10/16)=1

y=-4                                                 -2x+5=1

 

-x=2+(-4)                                             -2x=1-5

-x=2-4                                                    -2x=-4/-2

-x=-2/-1                                                    x=2

x=2  y=-4                                    y=10/16(dziesię szesnastych)