Question

[Trịnh Ngọc Bảo Long]

giúp mình với mình cần gấp 

Answer 1

[Yen Nhi]

`Answer:`

c) \(\frac{2\left(3x+5\right)}{3}-\frac{x}{x}=5-\frac{3\left(x+1\right)}{4}\)

\(\Leftrightarrow\frac{8\left(3x+5\right)}{12}-\frac{6x}{12}=\frac{60}{12}-\frac{9\left(x+1\right)}{12}\)

\(\Rightarrow24x+40-6x=60-9x-9\)

\(\Leftrightarrow24x+9x-6x=60-9-40\)

\(\Leftrightarrow27x=11\)

\(\Leftrightarrow x=\frac{11}{27}\)

d) \(x^2-4x+4\)

\(\Leftrightarrow x^2-2x-2x+4\)

\(\Leftrightarrow x\left(x-2\right)-2\left(x-2\right)\)

\(\Leftrightarrow\left(x-2\right)\left(x-2\right)\)

\(\Leftrightarrow\left(x-2\right)^2\)

e) \(\frac{x-1}{x+2}-\frac{x}{x-2}=\frac{5x-8}{x^2-4}\left(ĐKXĐ:x\ne\pm2\right)\)

\(\Leftrightarrow\frac{x-2}{x+2}-\frac{x}{x-2}=\frac{5x-8}{\left(x+2\right)\left(x-2\right)}\)

\(\Leftrightarrow\frac{\left(x-1\right)\left(x-2\right)}{\left(x+2\right)\left(x-2\right)}-\frac{x\left(x+2\right)}{\left(x-2\right)\left(x+2\right)}=\frac{5x-8}{\left(x+2\right)\left(x-2\right)}\)

\(\Leftrightarrow\left(x-1\right)\left(x-2\right)-x\left(x+2\right)=5x-8\)

\(\Leftrightarrow x^2-2x-x+2-x^2-2x=5x-8\)

\(\Leftrightarrow-5x+2=5x-8\)

\(\Leftrightarrow-10x=-10\)

\(\Leftrightarrow x=1\)