Odpowiedzi

2010-02-17T20:45:27+01:00
(7X-3Y):5=(5X-Y):3-(X+Y):2/×30
3(X-1)=5(Y+1)

6(7x-3y)=10(5x-y)-15(x+y)
3x-5y=8

42x-18y=50x-10y-15x-15y
42x-50x+15x=18y-10y-15y
7x=-7y/:7
x=-y

3×-y-5y=8
-3y-5y=8
-8y=8
y=8:-8
y=-1

x=-y
x=1

odp. x=1
y=-1