Answers

2015-07-12T20:27:45+08:00
X= + integer  y= - integer
x+y=4
x-y= 14  <------ distance

x+x=18
2x=18 
transpose 2 at the other side it gives
x= 18/2
x=9
y= 9-14= -5

+9 and -5 
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