SOLUTION: I am having trouble with 2 equations, Thanks! 1. 6 - 3x + 12 = 0 2. -7 + 5x = 10x - 2 3. 6y - 2 + 2y = 14 I know this is a lot but please help me, i just want to understand

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Question 29030: I am having trouble with 2 equations, Thanks!
1. 6 - 3x + 12 = 0
2. -7 + 5x = 10x - 2
3. 6y - 2 + 2y = 14
I know this is a lot but please help me, i just want to understand how it is done... im homeschooled and the books are not helping!
Thanks!
Jeff.
Answer by sdmmadam@yahoo.com(530) (Show Source):
You can put this solution on YOUR website!
I think I have answered this just a couple of minutes ago. May be the answer is not mailed.

I am having trouble with 3 equations, Thanks!
1. 6 - 3x + 12 = 0
2. -7 + 5x = 10x - 2
3. 6y - 2 + 2y = 14
1. 6 - 3x + 12 = 0
(6 - 3x) + 12 = 0 (by additive associativity)
(-3x+6)+12 =0 (by additive commutativity)
-3x+(6+12)=0 (again by additive associativity)
-3x+18 =0
+3x -3x+18 = 3x+0 (adding 3x from the left to both the sides)
(3x-3x)+18 =3x
(by additive associativity on the LHS and additive identity law on the RHS)
0+18=3x (by additive inverse law)
18 = 3x (by additive identity law)
Dividing by 3
(18/3)=x
(6X3)/3 = x
6=x (cancelling 3 in the nr and in the dr)
That is x=6
Answer:x=6
Note: All these steps you ought to do only if you are asked to give every step and the valid reasons for the steps. Otherwise you may follow the general rule of grouping like terms for the addition. And also subtraction is another form of addition. For instance subtracting px amounts to adding (-px).
Note:You may transfer a term or terms from one side to the other while grouping like terms. The only caution that you have to follow is: change side then change sign.
2. -7 + 5x = 10x - 2
-7+2 = 10x-5x
(transferring -2 from the right to the left and 5x from the left to the right.)
-5 = 5x
(-5)/5 =x
-1=x
That is x=-1
Answer: x= -1
3. 6y - 2 + 2y = 14
(6y+2y) =14+2
8y = 16
y =16/8 = 2
Answer: y=2