\(9x^2-30x+225=0\)

\(3x^2+12x-66=0\)

\(\left(x^2-9\right)^2-9\left(x-3\right)^2=0\)

Word-form

1.In my.......(live),i have never watched a more interesting film than this

2.Mai is......(little) intelligent than Nga

3.It is the.......... (much)difficult exercise I have ever done

4.Joans is a...............(visit)from England.She has visited Vietnam twice

5.My Linh is a famous..........(sing)