You can put this solution on YOUR website! 6-(3+x) is the same as 6-3-x simplied to 3-x
if set equal to 0 and solving for x
3-x=0
3-x+x=0+x
3=x
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7-(2x-3[1-x]) is the same as 7-(2x-3+3x), which is the same as 7-2x+3-3x
simplified to 10-x
if set equal to 0 and solving for x
10-x=0
10-x+x=0+x
10=x
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