Question 619927
You don't add 6 to both sides. You want to undo that +6 on the left side. So you subtract 6 from both sides


to go from


3x+6 = 30


to


3x+6 <font color="red">-6</font> = 30 <font color="red">-6</font>


Then notice how 6-6 on the left side becomes 0 and it goes away. On the right side, 30-6 becomes 24


So we then get


3x = 24


Now divide both sides by 3


3x<font color="red">/3</font> = 24<font color="red">/3</font>


x = 8


So the answer is x = <font color="red">8</font>