Odpowiedzi

2009-12-02T23:10:21+01:00
1.
(2u=5+v /:2
(2u=2+u

(u=2½+½v
(2(2½+½v)=2+2½+½v

(u=2½+½v
(5+v=4½+½v

(u=2½+½v
(½v=(-½) /*2

(v=(-1)
(2u=5-1 /:2

(v+(-1)
(u=2

3.
(5y+5=2y
(x+3y=2x

(3y=5 /:3
(3y=x

(y=3/5
(3*(3/5)=x

(y=3/5
(x=6/5

4.
(2c-3d=c-5
(c-d=15

(c=15+d
(2*(15+d)-3d=15+d-5

(c=15+d
(30+2d-3d-d=10

(c=15+d
(-2d=(-20) /:(-2)

(d=10
(c=15+10

(d=10
(c=25

7.
(x=20y
(x-20*x=y-2

(x=20y
(20y-400y=y-2

(x=20y
(-379y=-2 /:(-379)

(x=20y
(y=2/379

(x=40/379
(y=2/379

Zadanie 2. 5. i 6.
Nie mozna rozwiazac poniewaz albo zle jest przepisany przyklad albo sa 3 zmienne.