A

D

\(\sqrt{x^2-16}-2\sqrt{x-4}=0\left(đk:x\ge4\right)\)

\(\Leftrightarrow\sqrt{\left(x-4\right)\left(x+4\right)}-2\sqrt{x-4}=0\)

\(\Leftrightarrow\sqrt{x-4}\left(\sqrt{x+4}-2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}\sqrt{x-4}=0\\\sqrt{x+4}=2\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x-4=0\\x+4=4\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x=4\left(tm\right)\\x=0\left(ktm\right)\end{matrix}\right.\)

13 take => takes

14 homes => home

 1. My teacher gave me a notebook as a reward.

I was given a notebook as a reward by my teacher.

2. People pick grapes and then turn them into wine.

__Grapes are picked and turned into wine______

3. My father didn’t allow me to stay up late.

___I wasn't allowed to stay up late by my father_________

4. you don’t use pencils in your Maths exam.

_____Pencils don't be used in your Maths exam_________

5. My parents allowed me to go picnic with my friends yesterday.

______I was allowed to go picnic withs my friends by my parents yesterday__________

6. No one told me about his story.

_____I wasn't told about his story__________

7. I make this cake.

____This cake is made by me_______

8. When I was a kid, a dog bit my leg.

_____My leg was bitten by a dog when I was a child __________

9. You need many social skills when you enter the workplace. _______Many social skills are needed when you enter the workplace________.

10. A hearing aid assists my grandmother’s hearing.

_____My grandmother's hearing is assisted by a hearing aid_________

listening