x, y and z are integers and x=y-z , x+z > x-y?
a. x is negative
b. y is negative
The statement in other words is asking if z > -y
1 says that x is negative
x= y-z which says that y < z . that is .... z >y
but we do not know whether y is postive or negative
say z =-100 , y= -200
z > y , but z < -y
say z= 10 , y = 5
z> y and z> -5
2 says y is negative
X= Y-Z ..that is y = x + z ...here either one of them is negative or both of them is negative ...so we cant say for sure about the relationship between y and z.
say x= 100 , z =-200 ... y= -100 , z < -y
say x= -20 z =10 y = -10 , z = -y
say x= 0 , z = -1 y= -1 , z <-y
so we have no consistent solution
Combine them .... we have
x= y-z , we know x and y are negative...
we have z= y-x
y=-20 , x=-10 =>> z =-10 z <-y
y=-20 , x=-50 z = 30 z>-y
We have no consistent solution