You can put this solution on YOUR website! I think you're having the problem of distributive multiplication
see:
5x-7=2(x+3)
1.)distribute
5x-7=-7+2x+6
2.)combine like terms (-7+6=-1)
5x-7=-1+2x
3.)subtract -2x from both sides (2x&5x)
3x-7=-1
4.)divide three from both sides
x=?
--hope i helped
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