1) 22x-13<25x+12
22x-1<25x
X=1
2) (x+1) * (y+2)=42
(x+3) * (y+5)=72
X*y+2x+y+2=42
X*y+5x+3y+15=72
X*y+5x+3y=57
X*y+2x+y=40
Le scădem
3x+2y=13
(x,y)={(1,5),(3,2)}
3)
A) 70+x+70y+x= (1001x + 110y) :11+1
69+2x+70y= 91x + 10y
69+60y=89x
*=ori
Atat știu! Sper ca te-am ajutat!