14x-(2x-y)-y
First you must distribute through the negative in front of the parenthesis means the same as
14x- 1(2x-y)-y
so you must multiply 2x and -y by -1
-1* 2x= -2x
-1* -y= y ( two negatives equal a positive)
Now: 14x-2x+y-y (the y's cancel leaving-)
14x-2x
You're answer is 12x