SOLUTION: when solving 3x + 6 = 18, why do you add -6 under the 6 which makes 0 and add -6 under the 18, which makes 12? then it turns out to be 3x = 12, and x = 4. The problem I am having

Question 530055: when solving 3x + 6 = 18, why do you add -6 under the 6 which makes 0 and add -6 under the 18, which makes 12? then it turns out to be 3x = 12, and x = 4. The problem I am having is the signs, why do you use the negative 6?
Answer by rfer(16322) (Show Source): You can put this solution on YOUR website!
In order to remove the 6 from the left side it is necessary to do the opposite of what is there. In this case it is a +6 so you need to subtract to remove it.
In equations it is always necessay to do the same thing to both sides, thus 18-6=12.
Another thought, if you had 3x-6=18 you would add 6 to both sides to remove it from the left side. Always do the opposite to what is there.
Does that help?
Bob
RELATED QUESTIONS
Write a rule for the sequence. Then find the next three terms. 6, 8, 10, 12, . . .... (answered by josgarithmetic)

6+2x+6+2x=6(2x) I don't understand in which order to do this. I know how add and... (answered by jim_thompson5910)

how do you get the answer to this question 54-6/2+6=57 How do you get 57? You first... (answered by JBarnum,Alan3354,ChristyD.24)

simplify :- 12 under root 18 - 6 under root 20 - 3 under root 50 + 8 under root 45 (answered by stanbon)

this is my last problem i need help with. can someone please take a look. 6. Below are... (answered by stanbon)

we are studying this now so i figured this questions corresponds to it. here it is 1.... (answered by Fombitz)

I hope you can answer my problem. The -6 is actually under the complete top portion of... (answered by Nate)

27 ^ -2/3 ------------- 27 ^ -1/3 This is what I have done: I moved the bottom... (answered by jim_thompson5910)

Hi, I solved this quadratic equation but was not sure how to finalize my answer. I... (answered by stanbon)