A

1 A

2 D

3 A

4 B

5 A

6 A

7 C

8 C

9 D

10 D

B

1 D

2 D

3 C

4 B

5 C

6 A

7 A

8 C

9 A

10 A

muốn dc như vậy hơi khó :))

She has brown hair

tại thích dùng acc này nên cho acc kia bay :))

bay acc r e :))

1 Ms.Laura asked Mr Alan if he forgot talking with her at Ann's wedding party

2 Playing basketball is not as dangerous as playing ice hockey

Đặt \(\sqrt{x+3}=a\); \(\sqrt{y+1}=b\) (a,b \(\ge0\))

\(\Rightarrow\left\{{}\begin{matrix}a-2b=2\\2a+b=4\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}2a-4b=4\\2a+b=4\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}5b=0\\2a+b=4\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}b=0\\a=2\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}\sqrt{x+3}=2\\\sqrt{y+1}=0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=1\\x=-1\end{matrix}\right.\)(tmđk)

Vậy hệ pt có nghiệm suy nhất (x;y) = (1;-1)