.

BT. 

1. She is bad and a always wants to hurt people . She is _______.

A. evil                           B. harmful                         C. moral                    D. kind

1. She is bad and a always wants to hurt people . She is _______.

A. evil (xấu xa, ác quỷ)                          B. harmful (có hại)                         C. moral (thích hợp)                   D. kind (hiền lành)

BT. 

1. She is bad and a always wants to hurt people . She is _______.

A. evil                           B. harmful                         C. moral                    D. kind

What Time is the game news programme on?

Which channels do you have

Why can't I use this remote control?- Because it isn't working 

How often do you watch cartoons?- Two or three time a week

Where do you go school?- I go to Trung Vuong Lower Secondary scholl

When do you have English?- On Wednesday and Friday morning

How long are you playing the video game?- For an hour

...what... Time is the game news programme on?

...what/which... channels do you have

...why... can't I use this remote control?- Because it isn't working

...how often... do you watch cartoons?- Two or three time a week

...where... do you go scholl?- I go to Trung Vuong Lower Secondary scholl

....when.. do you have English?- On Wednesday and Friday morning

...how long... are you playing the video game?- For an hour

1) Ta có: \(\left(-5+x\right)\left(x-7\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}-5+x=0\\x-7=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=5\\x=7\end{matrix}\right.\)

Vậy: \(x\in\left\{5;7\right\}\)

2) Ta có: \(\left(30-x\right)\left(2x-16\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}30-x=0\\2x-16=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}-x=-30\\2x=16\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=30\\x=8\end{matrix}\right.\)

Vậy: \(x\in\left\{30;8\right\}\)

3) Ta có: \(\left(-5-x\right)\left(17+x\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}-5-x=0\\17+x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}-x=5\\x=0-17\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-5\\x=-17\end{matrix}\right.\)

Vậy: \(x\in\left\{-5;-17\right\}\)

4) Ta có: \(\left(-3x+18\right)\left(-5x-10\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}-3x+18=0\\-5x-10=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}-3x=-18\\-5x=10\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=6\\x=-2\end{matrix}\right.\)

Vậy: \(x\in\left\{6;-2\right\}\)

Bài nay ta có hai vế bạn hãy đặt giả sử một trong hai vế bằng 0 rồi giải phương trình cho mỗi vế bằng o

Trên tia Ox, ta có: OA<OB(4cm<8cm)

nên điểm A nằm giữa hai điểm O và B

\(\Leftrightarrow OA+AB=OB\)

\(\Leftrightarrow AB=OB-OA=8-4=4\left(cm\right)\)

Ta có: điểm A nằm giữa hai điểm O và B(cmt)

mà AB=OA(=4cm)

nên A là trung điểm của OB