Question

giải phương trình :

\(\dfrac{80}{x+4}\)+ \(\dfrac{80}{x-4}\) = \(\dfrac{25}{3}\)

 

 

Answer 1

\(\Leftrightarrow\dfrac{16}{x+4}+\dfrac{16}{x-4}=\dfrac{5}{3}\)

=>\(\dfrac{16x-64+16x+64}{x^2-16}=\dfrac{5}{3}\)

=>5(x^2-16)=3*32x=96x

=>5x^2-96x-80=0

=>x=20 hoặc x=-4/5