tổng hai nghiệm phương trình:\(^{x^4-5^2+6=0}\)là:

A.\(s=\left\{2;3\right\}\)

B.\(s=\left\{\pm\sqrt{2};\pm\sqrt{3}\right\}\)

C.\(s=\left\{\sqrt{2};\sqrt{3}\right\}\)

D.\(s=\left\{2;-3\right\}\)

linguistics is the science of_______

A.medicine

B.languages

C.economics 

D.mathematics

this is mrs .nga______taught me english when l was in grade 6

A.who

B.that

C.whow

D.whose

would you mind_________ the book l gave you last week?

A.return

B.to return

C.returning

D.returned

l still can't apply for a job          l have got a university degree on teaching

A.although

B.since

C.therefore

D.because

1.he is so                     that he ne never gets good mark

A .careful       B.care      C.careless      D.carelessly

2.the gegraply teacher asked me

A. where was the Europe on map       

B.// //  //  is // // // // // // //

C. where the Europe Was on the map

D.// // // //  //  // // // //  is // // // // // // //

giải hệ phương trình

\(\left\{{}\begin{matrix}-2x+y=2\\2x-2y=1\end{matrix}\right.\)