Oblicz równianie (załącznik)

[latex]dfrac{1}{10}=dfrac{1}{x}+dfrac{1}{30}\ dfrac{1}{x}=dfrac{1}{10}-dfrac{1}{30}\ dfrac{1}{x}=dfrac{3}{30}-dfrac{1}{30}\ dfrac{1}{x}=dfrac{2}{30}\ dfrac{1}{x}=dfrac{1}{15}\ x=15 [/latex]