розкласти на множники

100-9[2]=?????

х[2]-49y[2]=

4+4x+x[2]

упростить выражение 2(а-3)+6

Rewrite the sentences with have to,don't have to and mustn't .

1)It isn't necessary for you to come ,but you can if you want to.

 You______________________________________

2)We aren't allowed to stay in the classroom at lunchtime.

 We________________________________________

3)It doesn't matter if you don't finish your dinner.

  You______________________________________

Записать уравнение реакций... Al--AlCl3--Al(OH)3---Al2O3---Al