12+5v−12−<span>2v</span>=2v−9−12−<span>2<span>v Step 1
</span></span>12−12+5v−<span>2v</span>=2v−<span>2v</span>−9−<span>12. Step 2
</span>0+<span>(5−2)</span>v=0−<span>21. Step 3
</span>3v=−<span>21 Step 4
Now you have to divide
</span><span><span>3v</span>3</span>=−<span>21<span>3
</span></span>
<span><span><span>3v</span>3</span>=−7</span>
<span><span>v=−7</span>
</span>
