x, y and z nonzero numbers - DS (>700)

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x, y and z nonzero numbers - DS (>700)

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If x, y and z are nonzero numbers, is ?

(1)

(1)
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C

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Luke
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Re: x, y and z nonzero numbers - DS (>700)

Mensaje por Luke »

(1) This expression means that both x and y are >0. In that case, the value of the product depends on the value of z.
If z>0, (y+z) can be >0;<0;=0, depending on the value of z vs value of y. As we don't know anything abut z (only z<>0), this is not sufficient.

(2) This expression means that both y and z are >0. In that case, the product will be positive if X>0 and will be negative if x<0. As we only know x<>0, this is not sufficient.

Together, we know x,y and z are >0, so the product is always positive.

C is the answer

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lox
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Re: x, y and z nonzero numbers - DS (>700)

Mensaje por lox »

|-3 + (- 5)| = |-3| + |-5| :P

fredurst
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Re: x, y and z nonzero numbers - DS (>700)

Mensaje por fredurst »

abs(x+y)=abs(x)+abs(y) if x,y are both neg o positive. But the answer to this questions stays the same. C

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