Упростите выражение а^2+у^2/ау-у^2 - 2а/а-у.

( / - черта дроби. деление как-бы.)

Постройте график функции а) у= -0,5х^2
б) проходит-ли график через точку М (8:-32.)

Помогите пожалуйста!^_^

 Find the mistakes and correct them. Answer the questions.

1.    Do more people speak the Chinese or the English?
2.    Which is the largest country in the world?
3.    Is the Africa larger than the Europe?
4.    Which sea is smaller, the Baltic Sea or the Black Sea?
5.    Are the Himalayas or the Alps the highest mountains in the world?
6.    The deepest lake in the world is the Lake Ontario, isn't it?
7.    Is the Caspian Sea or the Dead Sea the saltiest in the world?
8.    Is the Amazon shorter than the Nile?
9.    Does the Nile flow through the Egypt or through the Iran?