$\begin{array} \; 34x-18=10x-9\\ {\underline{\; \; 10x \quad \; \; \, = -10x \quad}} \quad \text{Subtract }10x\ \text{from each sides}\\ 24x-18= -9 \end{array}$

$24x−18=-9\\ {\underline{\qquad +18 = +18}} \quad \text{Add 18 to both sides}\\ \qquad \; 24x=9$

$24x=9\quad\text{ (Divide both sides by 24)}$

$x=\frac{9}{24} = \frac{3}{8} = 0.375$

No solution.

$3x-15+6x+2=45$

Remember to combine only like terms.