Question 269664
Hello, 
Let's rewrite this 5x-y-12-(-x+y-10)  as:
5x-y-12-1(-x+y-10) Now we can multiply -1 in each term in the parenthesis to be:
5x-y-12+x-y+10 Now combine like terms to get:
6x-2y-2
There we go. 
RJ
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