elementary math
posted by anna .
i did use my poof to prove. im not sure im doing right.
here is exercises:
'Suppose a,b,c are integers if ab and ac, then a(b+c).'
my answer:
Proof. Suppose ab ans ac.
By Definition of divisibility. we know ab means there is an integer x with b= ax.
Likewise, ac means there is an integer y for which c= ay
Thus b+c=(ax+ay)= a(x+y)
therefore a(b+c).
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