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Najlepsza Odpowiedź!
2009-12-10T21:44:02+01:00
A)
{x+3y=3
{x-y=5

x=3-3y
3-3y-y=5

x=3-3y
-4y=5-3

x=3-3y
-4y=2 / : [-4]

x=3-3y
y= 1/2

x=3-3 * 1/2
y= 1/2

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

x=1,5
y=1/2


b)
{5y=2 / :5
{x+y=2 2/5

y= 2/5
x+2/5=2 2/5

y= 2/5
x=2 2/5 - 2/5

y=2/5
x=2

Miałam to ;). Na pewno dobrze ;]
2009-12-10T21:50:53+01:00
A)
{x + 3y = 3
{x - y = 5 | *3

{x + 3y = 3
{3x - 3y = 15
+______________
4x =18 | :4
x = 4,5

4,5 + 3y = 3
3y = -1,5
{y = (-0,5)
{x = 4,5

b)
{5y = 2 |*(-1)
{x + y = 2 |*5

{-5y = -2
{5x + 5y = 10
+____________
5x = 8 |:5
x = 1,6

1,6 + y = 2
{y = 0,4
{x = 1,6