a)
\(\begin{array}{l}\,\,\,2x - 3 = - 3x + 17\\2x + 3x = 17 + 3\\\,\,\,\,\,\,\,\,\,\,\,5x = 20\\\,\,\,\,\,\,\,\,\,\,\,\,\,x = 20:5\\\,\,\,\,\,\,\,\,\,\,\,\,\,x = 4\end{array}\)
Vậy \(x = 4\) là nghiệm của phương trình.
b)
\(\begin{array}{l}\frac{2}{3}x + 1 = - \frac{1}{3}x\\\frac{2}{3}x + \frac{1}{3}x = - 1\\x = - 1\end{array}\)
Vậy \(x = - 1\) là nghiệm của phương trình.
c)
\(\begin{array}{l}\,0,15\left( {t - 4} \right) = 9,9 - 0,3\left( {t - 1} \right)\\\,0,15t - 0,6 = 9,9 - 0,3t + 0,3\\0,15t + 0,3t = 9,9 + 0,3 + 0,6\\\,\,\,\,\,\,\,\,\,\,\,\,\,0,45t = 10,8\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,t = 10,8:0,45\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,t = 24\end{array}\)
Vậy \(t = 24\) là nghiệm của phương trình.
d)
\(\begin{array}{l}\,\,\,\,\,\,\,\,\,\,\,\,\,\frac{{3z + 5}}{5} - \frac{{z + 1}}{3} = 1\\\frac{{3\left( {3z + 5} \right)}}{{15}} - \frac{{5\left( {z + 1} \right)}}{{15}} = \frac{{15}}{{15}}\\\,\,3\left( {3z + 5} \right) - 5\left( {z + 1} \right) = 15\\\,\,\,\,\,\,\,\,\,\,9z + 15 - 5z - 5 = 15\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,9z - 5z = 15 - 15 + 5\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,4z = 5\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,z = \frac{5}{4}\end{array}\)
Vậy \(z = \frac{5}{4}\) là nghiệm của phương trình.