\(5^{2x-7}=5^{13}\)

\(\Rightarrow2x-7=13\)

\(\Rightarrow2x=13+7\)

\(\Rightarrow2x=20\)

\(\Rightarrow x=20:2\)

\(\Rightarrow x=10\)

\(\frac{5}{2}\left(x-\frac{3}{5}\right)-\frac{1}{10}=x-3\)

\(\frac{5}{2}x-\frac{3}{2}-\frac{1}{10}=x-2\)

\(\frac{5}{2}x-\frac{15}{10}-\frac{1}{10}=x-2\)

\(\frac{5}{2}x-\frac{7}{5}=x-2\)

\(\frac{5}{2}x-\frac{7}{5}-x+2=0\)

\(x\left(\frac{5}{2}-1\right)-\frac{7}{5}+\frac{10}{5}=0\)

\(\frac{3}{2}x+\frac{3}{5}=0\)

\(\frac{3}{2}x=\left(-\frac{3}{5}\right)\)

\(x=\left(-\frac{3}{5}\right):\frac{3}{2}\)

\(x=\left(-\frac{3}{5}\right).\frac{2}{3}\)

\(x=\left(-\frac{2}{5}\right)\)

1- A. Coummunity 
2- B non-profit (Tính từ: Phi lợi nhuận)

3- C tutor
4- B difference

Cảm ơn bạn Nguyễn Minh Tuấn nhiều nha

ab200

\(\left|x\right|\ge0\)

\(\Rightarrow\frac{-1}{\left|x\right|+1}\ge\frac{-1}{0+1}=-1\)

Dấu bằng khi x = 0

TL:

. A. third B. thirteen C. thirteenth D. thirties

. A. is B. have C. stay D. be

. A. Her B. His C. Their D. Our

. A. could B. shall C. will D. would

 A. be B. is C. are D. has

^HT^

V. Đọc đoạn văn sau và chọn đáp án thích hợp điền vào chỗ trống.

21.  thirteenth 

22.  stay

23.   His

24.   will 

25.   is 

\(\frac{9^5.27^3}{3^{18}}\)

\(=\frac{\left(3^2\right)^5.\left(3^3\right)^3}{3^{18}}\)

\(=\frac{3^{10}.3^9}{3^{18}}\)

\(=\frac{3^{19}}{3^{18}}=3\)

9 mũ 5 với 27 mũ 3 nhé

b) \(1,6-\left|x-0,2\right|=0\)

\(\Leftrightarrow\left|x-0,2\right|=1,6\)

\(\Leftrightarrow\orbr{\begin{cases}x-0,2=1,6\\x-0,2=-1,6\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=1,8\\x=-1,4\end{cases}}\)

a) \(\frac{-7}{15}.\frac{5}{8}.\frac{15}{-7}.\left(-32\right)\)

\(=\frac{5}{8}.\left(-32\right)\)

\(=-20\)