Subtract 14x from both sides to get
[tex] 20x-14x+12 \geq 30 [/tex]
Subtract 12 from both sides to get
[tex] 20x-14x \geq 30-12 [/tex]
Now we have moved all terms involving x on one side, and all constant terms on the other. We can simplift both sides, i.e. sum like terms, to get
[tex] 6x \geq 18 [/tex]
Now we have to divide both sides by 6. When dealing with inequality you have to be careful about dividing both sides by the same constant: if the constant is negative, the inequality side switches (i.e. [tex] \geq \leftrightarrow \leq [/tex]). But this is not the case since 6 is positive, so we mantain the inequality sign:
on the other. We can simplift both sides, i.e. sum like terms, to get
[tex] \cfrac{6x}{6} \geq \cfrac{18}{6} [/tex]
Evaluate left and right hand side:
[tex] x \geq 3 [/tex]
