Friday, September 10, 2010

Is (m + z) > 0?

1) m - 3z > 0

2) 4z - m > 0




1 tells m > 3z , not suffecient
2 tells z > m/4 not sufficient.

Add both the ineq's (Add is fine). Gives z > 0
since m > 3z, z>0 so m>0

Hence m+z > 0

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