Tìm x, biết a) x + 2/3 = -3/4 b) 5/4 - x = -3/2

* Hướng dẫn giải

$\begin{array}{l}\text{a) }x+\frac{2}{3}=\frac{-3}{4}\\ x=\frac{-3}{4}+\frac{2}{3}\\ x=\frac{-9}{12}+\frac{8}{12}\\ x=\frac{-1}{12}\end{array}$

$\begin{array}{l}\text{b) }\frac{5}{4}-x=\frac{-3}{2}\\ x=\frac{5}{4}-\frac{-3}{2}\\ x=\frac{5}{4}+\frac{6}{4}\\ x=\frac{11}{4}\end{array}$