Your first two steps are fine. On the third, in which you go from
12x - 12 = 10x - 43
to
-12 = -2x - 43
I think you mean to say you're subtracting 12x from each side.
Adding 43 to each side leaves 31 = -2x.
Divide each side by -2 to get x = (-31)/2.
So, it looks like you were right, except for dropping a - when subtracting 43.
9x+3(x-4)=10(x-5)+7
9x+3x-12=10x-50+7
12x-12=10x-43
subtract -12 from both sides and that leaves
-12=-2x-43
add 43 to both sides and that leaves 31=2x
then the answer is x=31/2 (a fraction)
im so confused and its even harder trying to type it out and not confuse anyone reading it. lol
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