Part 1: sqrt(xz) is an integerHG10 wrote:If z is a positive integer, is root z an integer?
1. Root (xz) is an integer
2. x = z^3
OA: E
Examples make this easy...
x = 1 AND z = 4. sqrt(4) = 2
x = 2 and z = 2. sqrt(2) NOT an integer
INSUFFICIENT
Part 2: x = z^3
This puts no restrictions on z. INSUFFICIENT
(1) and (2)
Combining the formulas for parts 1 and 2, we get sqrt(z^4) is an integer, which again has no restriction on z, since z^2 of any integer is an integer.
INSUFFICIENT
E
