Tìm x:
a)2x.(x-5)=2x²+x-11
b)x³-6x²+9x=0
c)x.(x-2018)-2017x+2017.2018=0

Tính:
a)(x-2).(x+2)-(x²-2x-4)
b)(x²-10xy+25y²):(5y-x)
c)(28x-9x³+x³-30):(x-3)

Phân tích đa thức thành nhân tử:
a)-5x+20x²
b)-x²+2x-1+y²
c)6x²-x-2

Rewrite each of the following sentences in another way so that it means almost the same as the sentnce printed before it.
33.The man was not rich.He couldn't buy a new bike.(enough)
=>The man wasn't
34.No one helped him wash the car.(Reflexive pronoun)
=>He
35.I was in Ha Noi when I was ten years old.(used to)
=>I used
36.It took my sister thirty minutes to install my computer.
=>My sister spent