Question 176323
Let's assume that {{{a-b-c=a-(b-c)}}} 



{{{a-b-c=a-(b-c)}}} Start with the given equation.



{{{a-b-c=a-b+c}}} Distribute the negative. Remember, this negative applies to EVERYTHING in the parenthesis. So change the sign of "b" to get "-b" and change the sign of "-c" to get "c"


{{{-b-c=-b+c}}} Subtract "a" from both sides.



{{{-c=c}}} Subtract "b" from both sides.



Because the equation above is NOT true for all values of "c" (in fact, it's only true if {{{c=0}}}), this means that {{{a-b-c=a-(b-c)}}} is NOT true.