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
are integers, then we have four possibilities:Y=13, \,Z=1, \, Y-Z=12Y=-13, \,Z=-1, \,Y-Z=-12Y=1, \,Z=13, \, Y-Z=-12Y=-1, \,Z=-13, \, Y-Z=12
you will get the same value for X
for all the above solutions.
PhD in Applied Mathematics
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