Question

a) x + 2/5 - 2y = 5

x - y+2/6 = 3

b) x + y/2 - x/3 = 4

x - y/2 + y/3 = -3

c) 3x-1/5 + 2y-3/4 = 3(y+1)/2

x+y/4 - 3y-1/2 = x-6y/4

d) 3x-2/3 - 2x+y/6 = x+1/6

x+y - (-x+y)/5 = 1/5 - 0,8 x

To jest zadanie 10/103 str z matematyka z plusem dla 2 gimnazjum

za odpowiedzi typu nie wiem / jeszcze niebraliśmy, daje spam

Answer 1

a) x + 2/5 - 2y = 5

x - y+2/6 = 3

 

x-2y=5-2/5

x-y=3-2/6

 

x-2y=4 3/5

x-y=2 4/6

 

x-2y=4 3/5

x=2 2/3+y

 

2 2/3+y-2y=4 3/5

x=2 2/3+y

 

-y=4 3/5 - 2 2/3

x=2 2/3+y

 

-y=4 9/15 - 2 10/15

x=2 2/3+y

 

-y=1 14/15/:(-1)

x=2 2/3+y

 

y=-1 14/15

x=2 2/3- 1 14/15

 

y=-1 14/15

x=2 10/15 - 1 14/15

 

y=-1 14/15

x=11/15

 

b) x + y/2 - y/3 = 4

x - y/2 + y/3 = -3/:(-1)

 

 x + y/2 - y/3 = 4

-x+y/2+y/3=3

 2 y/2=7

y=7

 

x+7/2-7/3=4

x+21/6-14/6=4

x+7/6=4

x=4-7/6

x=4-1 1/6

x=2 5/6

 

 

c) 3x-1/5  + 2y-3/4 = 3(y+1)/2

x+y/4 - 3y-1/2 = x-6y/4 /*4

 

3x+2y-4/20-15/20=3y+3 /2

4x+y-12y-2=x-6y

 

3x+2y-19/20=3y+3 /2  /*2

4x-11y-x+6y=2

 

6x+4y-19/10=3y+3

3x-5y=2

 

6x+4y-3y=3+1 9/10

3x-5y=2

 

6x+y=4 9/10

3x-5y=2

 

y=4 9/10-6x

3x-5(49/10-6x)=2

 

y=4 9/10-6x

3x-24,5+30x=2

 

y=4 9/10-6x

33x=2+24,5

 

y=4 9/10-6x

33x=49/2 /:33

 

y=4 9/10-6x

x=49/66

 

y=4 9/10-6*49/66

x=49/66

 

y=4 9/10-49/11

x=49/66

 

y=4 9/10-4 5/11

x=49/66

 

y=4 99/110 - 4 50/110

x=49/66

 

y=49/110

x=49/66

 

 

 

d)  3x-2/3 - 2x+y/6 = x+1/6 

x+y - (-x+y)/5 = 1/5 - 0,8 x  

 

6x-4/6 - 2x+y/6= x+1/6 /*6

x+y+x-y/6=1/5-0,8x /*6

 

6x-4-2x+y=x+1

x+6y+6x-y=6/5-4,8x

 

4x+y-x=1+4

7x+5y+4,8x=1 1/5

 

3x+y=5

11,8x+5y=1 1/5

 

y=5-3x

11,8x+5y=1 1/5

 

y=5-3x

11,8x+5(5-3x)=1 1/5

 

y=5-3x

11,8x+25-15x=1 1/5

 

y=5-3x

-3,2x=1 1/5-25

 

y=5-3x

-3,2x= -23 4/5 /:(-3,2)

 

y=5-3x

x=119/5 : 16/5

 

y=5-3x

x=119/5 * 5/16

 

y=5-3x

x=119/16

 

y=5-3x

x=7 7/16

 

y=5-3*119/16

x=7 7/16

 

y=5-357/16

x=7 7/16

 

y=5-22 5/16

x=7 7/16

 

y=17 5/16

x=7 7/16