Question

Proszę o rozwiązanie.

1. x+5/5 - y-2/2=4
x-3/3- 2-y/6=2
( oba w klamry)

2. x+2/2 - y-2/4 = 3
x-2/2 - 3y+1/7 = 0

3. x+6/3 + 3y+1/2 = 5
y+1/2 + x+5/8 = 2

Z góry dzięki. :)

Answer 1

1)

x+5/5 - y-2/2=4  /*10
x-3/3- 2-y/6=2  /6

 

2x+10-5y+10=40

2x-6-6+3y=12

 

2x-5y=40-10-10

2x+3y=12+6+6

 

2x-5y=20

2x+3y=24 /*(-1)

 

2x-5y=20

-2x-3y=-24

 

98y=-4  /:(-8)

y=4/8

y=1/2

y=0,5

 

2x-5*0,5=20

2x-2,5=20

2x=20+2,5

2x=22,5 /:2

x=11,25

 

y=0,5

x=11,25

2)

x+2/2 - y-2/4 = 3  /*4
x-2/2 - 3y+1/7 = 0  /*14

 

2x+4-y+2=12

7x-14-6y-2=0

 

2x-y=6  /*(-6)

7x-6y=16

 

-12x+6y=-36

7x-6y=16

 

-5x=-20 /:(-5)

x=4

 

7*4-6y=16

28-6y=16

-6y=16-28

-6y=-12 /:(-6)

y=2

 

x=4

y=2

3)

x+6/3 + 3y+1/2 = 5  /*6
y+1/2 + x+5/8 = 2  /*8

 

2x+12+9y+3=30

4y+4+x+5=16

 

2x+9y=15

4y+x=7

 

2x+9y=15

x=7-4y

 

2*(7-4y)+9y=15

14-8y+9y=15

-8y+9y=15-14

y=1

 

2x+9*1=15

2x+9=15

2x=15-9

2x=6 /:2

x=3