Question

a,\(\dfrac{x+1}{2x+1}\)=\(\dfrac{0.5x+2}{x+3}\)

b,|9-7x|=5x-3

c,|10x+7|<37

Các bạn giúp mình với!!!

Answer 1

a: \(\Leftrightarrow x^2+4x+3=x^2+4x+0.5x+2\)

=>0,5x+2=3

=>0,5x=1

hay x=2

b: \(\Leftrightarrow\left|7x-9\right|=5x-3\)

\(\Leftrightarrow\left\{{}\begin{matrix}x>=\dfrac{3}{5}\\\left(7x-9-5x+3\right)\left(7x-9+5x-3\right)=0\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x>=\dfrac{3}{5}\\\left(2x-6\right)\left(12x-12\right)=0\end{matrix}\right.\Leftrightarrow x\in\left\{3;1\right\}\)

c: =>10x+7>-37 và 10x+7<37

=>10x>-44 và 10x<30

=>-4,4<x<3