If xy + z = x(y + z), which must be true?

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If xy + z = x(y + z), which must be true?

by rd85 » Thu Jul 16, 2009 2:21 am
If xy + z = x(y + z), which must be true?
a. x = 0; z = 0
b. x = 1; y = 1
c. y = 1; z = 0
d. x = 1 or y = 0
e. x = 1 or z = 0

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by nitya34 » Thu Jul 16, 2009 3:16 am
z(1-x)=0

B it is?
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by rd85 » Thu Jul 16, 2009 5:07 am
OA is E :(

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Solution to the above problem..

by struggling_guy2001 » Thu Jul 16, 2009 5:14 am
Given statement:

xy+z= x(y+z)

==> xy+z = xy+xz.

Cancelling xy on both the sides and moving z to other side the equation becomes...

xz-z=0

==> z(x-1) =0

==> z=0 or x=1... Hence E is the answer for the above problem..

Hope it is clear...
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by rd85 » Fri Jul 17, 2009 5:44 am
Thanks a lot. Appreciate your help!