Odpowiedzi

2010-04-10T11:37:11+02:00
1)
7x-3y=15
x=15+3y÷7
7(15+3y/7)-3y=15
15+3y-3y=15
0=0
b)
2x+3y=-2
x=-2-3y/2
2(-2-3y/2)+3y=-2
-2-3y+3y=-2
0=0
c)
5x+6y=27
5x=27-6y /5
x=27-6y/5
5(27-6y/5)+6y=27
27-6y+6y=27
0=0
d)
3x-y=8
x=8+y/3
3(8+y/3)-y=8
8+y-y=8
0=0