Giải thích các bước giải:
\(\begin{array}{l}
a)\,\left| x \right| = \frac{3}{5} \Rightarrow x = \pm \frac{3}{5}\\
b)\,x:3 = 4:5 \Rightarrow x = 4:5 \times 3 = \frac{{12}}{5}\\
c)\, - \frac{3}{{14}} = \frac{{12}}{x} \Rightarrow x = 12:\left( { - \frac{3}{4}} \right) = - 16\\
d)\,\,\frac{{x + 2}}{{20}} = \frac{x}{{30}} \Rightarrow 30\left( {x + 2} \right) = 20x \Rightarrow 10x = - 60\\
\Rightarrow x = - 6\\
e)\,\frac{x}{{ - 12}} = \frac{{ - 3}}{x} \Rightarrow x.x = \left( { - 3} \right).\left( { - 12} \right) = 36 \Rightarrow x = \pm 6\\
f)\,\frac{{64}}{{{2^x}}} = 32 \Rightarrow {2^x} = \frac{{64}}{{32}} = 2 \Rightarrow x = 1\\
g)\,{27^x} = 81 \Rightarrow {3^{3x}} = {3^4} \Rightarrow 3x = 4 \Rightarrow x = \frac{4}{3}\\
h)\,\frac{{{3^x}}}{{27}} = 81 \Rightarrow {3^x} = 81.27 = {3^4}{.3^3} = {3^7} \Rightarrow x = 7\\
i)\,{\left( {x - \frac{1}{2}} \right)^2} = 0 \Rightarrow x - \frac{1}{2} = 0 \Rightarrow x = \frac{1}{2}\\
k)\,{\left( {2x - 1} \right)^3} = - 8 \Rightarrow 2x - 1 = {\left( { - 2} \right)^3}\\
\Rightarrow 2x - 1 = - 2 \Rightarrow 2x = - 1 \Rightarrow x = \frac{{ - 1}}{2}
\end{array}\)
