3.3 Lösning 2c
Från Mathonline
\(\begin{array}{rclcl} 2\,x \, + \, 12 & = & 18 & \qquad | & - \, 12 \\ 2\,x \, + \, 12 \,- \, 12 \, & = & 18 \, - \, 12 \, & & \\ 2\,x & = & 6 & \qquad | & / \, 2 \\ \displaystyle \frac{2\,x}{2} & = & \displaystyle \frac{6}{2} & & \\ x & = & 3 \end{array}\)
