Đáp án:
b) x=4
Giải thích các bước giải:
\(\begin{array}{l}
a)3\dfrac{1}{2} - \dfrac{1}{2}x = \dfrac{2}{3}\\
\to \dfrac{1}{2}x = \dfrac{7}{2} - \dfrac{2}{3}\\
\to \dfrac{1}{2}x = \dfrac{{17}}{6}\\
\to x = \dfrac{{17}}{3}\\
b)3.2x - \dfrac{1}{2}x + 2.7 = 4.9\\
\to \dfrac{{11}}{2}x = 36 - 14\\
\to \dfrac{{11}}{2}x = 22\\
\to x = 4
\end{array}\)