Given that X = (Y–Z)^2.What is the value of X?
(1) the product of Y and Z is 13
(2) Y and Z are non zero integers.
stmt (1) & stmt (2) aren't sufficient by themselves.
Combining the two, we see that since product of X,Y : XY=13 and X,Y are Non Zero integers.
So X, can take the values +1/-1 & +13/-13.
in any case X= Y^2+Z^2-2YZ.
Thus we can get a precise value for X by combining the 2 equations.
The OA is below. is this approach is okay ?
(1) and (2)
\(YZ=13\) and both \(Y\) and \(Z\) are integers, then we have four possibilities:
\(Y=13, \,Z=1, \, Y-Z=12\)
\(Y=-13, \,Z=-1, \,Y-Z=-12\)
\(Y=1, \,Z=13, \, Y-Z=-12\)
\(Y=-1, \,Z=-13, \, Y-Z=12\)
Since \(X=(Y-Z)^2\) you will get the same value for \(X\) for all the above solutions.
PhD in Applied Mathematics
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