Odpowiedzi

2009-12-12T13:18:00+01:00
A) x=y
5x-y=4

5y-y=4
x=y

4y=4 /:4
x=y

y=1
x=1


b) y=2x+1
4x+y=13

4x+2x+1=13
y=2x+1

4x+2x=13-1
y=2x+1

6x=12 /6
y=2x+1

x=2
y=2*2+1

x=2
y=5


c) 5y - x = 3
x = 3 - y

5y-(-3-y)=3
x=3-y

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

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

6y=6 /:6
x=3-y

y=1
x=2

Proszę bardzo :*
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