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how do i find the answer to 3x-12=-2x+83

i do not understand how to find the answer to the equation above 

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Matthew M. | Law Grad Tutors Writing, Test Prep, and More!Law Grad Tutors Writing, Test Prep, and ...
When you have the same variable on both sides of the equation you want to start by isolating the variable (in this case x) on one side.
I would start by adding 12 to each side
-12+12 cancels out to zero and you add 12 to 83
This leaves you with 3x=-2x+95
Next add 2x to each side
-2x+2x cancels out to zero
This leaves you with 5x=95
Now divide each side by 5
5/5=1 which leaves you with 1x or just x if you prefer. 95/5=19
Therefore you answer is x=19
Hope this helps.
Rebecca A. | Physics and Math: BeckaPhysics and Math: Becka
4.9 4.9 (13 lesson ratings) (13)
The following should help you work towards the answer.
1. Let us first put all of the constant terms together. The constants are the numbers without a variable. In this equation they are the -12 and 83.
Let us add 12 to the left side of the equation, since -12+12 will equal 0. Of course if we add 12 to the left side, we also need to add 12 to the right side.
   +12=     +12
Now the equation is:    3x=-2x+95
2. Let us now put the x values together. Above we added 12 since we knew -12+12=0. For the x values I am going to add 2x to the right side, since -2x+2x=0. Of course if we add 2x to the right side, we have to also add 2x to the left side.
Now the equation is:    5x=95
3. Let us "undo" the 5 times x. The equation 5x=95 is a simple way of saying x+x+x+x+x=95, which means that 5 x's will make 95. If I want each x to have an equal piece of 95, then I will have to divide 95 into 5 equal parts. Therefore I will divide 95 by 5.
5  = 5
4. Check!!! Go back and plug 19 in for the x value and make sure it works.