Question 338204
solve 
(Z+5)-7=(Z-7)+5 
Z+5-7 = Z-7+5
Z-2 = Z-2
Z = Z
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The original equation is an identity and
is true for all values of Z.
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and 
-(Y+5)-(2+7y)+8y=3y-8
-Y-5 -2-7y+8y = 3y-8
-7 = 3y-8
3y = 1
y = 1/3
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Cheers,
Stan H.