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number properties

Expert replies
Source: — Problem Solving |

by shibal » Mon Jul 06, 2009 6:31 pm
XY + Z = X(Y+Z) is the same as xy+z=xy+xz right?
it'll be the same as z=xz (minus xy in both sides).
therefore, to z =xz will only happen if x is 1 or z is 0...
hope it helps
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by Sid_Backlash » Mon Jul 06, 2009 11:18 pm
when u arrive at z=xz

u can further go algebraically.

xz = z
xz - z = 0

z(x-1) = 0

either z=0 or (x-1) = 0

means either z=0 or x=1
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