Đáp án:
d) \(x = \dfrac{{79}}{{28}}\)
Giải thích các bước giải:
\(\begin{array}{l}
a)\dfrac{{15\left( {2x - 3} \right) + 20\left( {x + 1} \right) - 12\left( {5x - 2} \right)}}{{60}} = 0\\
\to 30x - 45 + 20x + 20 - 60x + 24 = 0\\
\to - 10x = 1\\
\to x = - \dfrac{1}{{10}}\\
b)\dfrac{{4\left( {x - 1} \right) - 10\left( {2x + 3} \right) - 15x}}{{20}} = 0\\
\to 4x - 4 - 20x - 30 - 15x = 0\\
\to 31x = - 34\\
\to x = - \dfrac{{34}}{{31}}\\
c)\dfrac{{3\left( {3x - 2} \right) + 4\left( {2x + 5} \right) - 6\left( {x - 4} \right)}}{{12}} = 0\\
\to 9x - 6 + 8x + 20 - 6x + 24 = 0\\
\to 11x = - 38\\
\to x = - \dfrac{{38}}{{11}}\\
d)\dfrac{{15\left( {2x + 6} \right) - 12\left( {3x - 4} \right) - 10\left( {5x - 2} \right)}}{{60}} = 0\\
\to 30x + 90 - 36x + 48 - 50x + 20 = 0\\
\to 56x = 158\\
\to x = \dfrac{{79}}{{28}}
\end{array}\)
