Question

tìm x biết 

4x^2-25/2x-5=0

Answer 1

ĐKXĐ:\(2x-5\ne0\Rightarrow x\ne\dfrac{5}{2}\)

\(\dfrac{4x^2-25}{2x-5}=0\\ \Leftrightarrow\dfrac{\left(2x-5\right)\left(2x+5\right)}{2x-5}=0\\ \Leftrightarrow2x+5=0\\ \Leftrightarrow x=-\dfrac{5}{2}\left(tm\right)\)

Answer 2

\(\dfrac{4x^2-25}{2x-5}\)

\(=\dfrac{\left(2x-5\right)\left(2x+5\right)}{2x-5}\)\(=2x+5=0\)

\(\Rightarrow x=-\dfrac{5}{2}\)