Cześć ;-)
Zadanie 1
[tex]1 \ kg=100 \ dag\\\\50 \ dag=\frac{50}{100} \ kg=\frac{50:50}{100:50} \ kg=\boxed{\frac{1}{2} \ kg}[/tex]
Zadanie 2
[tex](3x+3)\cdot4(x+5)=(3x+3)\cdot(4x+20)=\\\\=12x^2+60x+12x+60=\boxed{12x^2+72x+60}[/tex]
Pozdrawiam! ~ JulkaOdMatmy
