Tìm x biết ​(begin{array}{l} – frac{1}{3}x – frac{1}{4} = frac{5}{3} end{array})

Ta có:

(begin{array}{l} – frac{1}{3}x – frac{1}{4} = frac{5}{3}\ – frac{1}{3}x = frac{5}{3} + frac{1}{4}\ – frac{1}{3}x = frac{{23}}{{12}}\ x = frac{{23}}{{12}}:left( { – frac{1}{3}} right)\ x = – frac{{69}}{{12}} = – frac{{23}}{4} end{array})