Question

dane sa uklady rownan : 1. x+y-4=0 3x-y=0 2. 2x+y=3 -2x+y=2 zad3 str 213. tabelki.

Answer 1

1.

 

x+y-4=0

3x-y=0

 

x=4-y

3(4-y)-y=0

 

x=4-y

12-3y-y=0

 

x=4-y

-4y=-12

 

x=4-3

y=3

 

x=1

y=3

 

2.

 

2x+y=3

-2x+y=2

 

y=3-2x

-2x+3-2x=2

 

y=3-2x

-4x=-1

 

y=3-2·1/4

x=1/4

 

y=3-1/2

x=1/4

 

y=5/2

x=1/4