We have to simplify 6x-(3x-7)+1. First we have multiply -1 (invisible -1 in front on parenthesis) by each argument inside the parenthesis.
Lets do this
6x-(3x-7)+1=6x+(-1)*(3x)+(-1)*(-7)+1=6x-3x+7+1
Now we can simplify 6x with -3x and 7 with 1 to get
6x-3x+7+1=3x+8 - its our result
1. Find the claim.
2. Look for fallacious reasoning.
3. Look for valid evidence supporting the claim.