Please help will give medal and fan !!

Find the counterexample to this statement: If xy = 0, then y must be equal to 0.

Select one:
a. x(0) = 0
b. (0)(0) = 0
c. (0)y = 0
d. (1)(1) = 1

Question

Please help will give medal and fan !!

Find the counterexample to this statement: If xy = 0, then y must be equal to 0.

Select one:
a. x(0) = 0
b. (0)(0) = 0
c. (0)y = 0
d. (1)(1) = 1

whpalmer4 · Answer

Hint: 2*0 = 0, and 0*2 = 0

anonymous · Answer

im still confused. :/

whpalmer4 · Answer

Well, okay.  Is $y=0$ the only way that you can have $x*y = 0$?

whpalmer4 · Answer

It seems to me that you can have $y = 2$ and still have $x*y = 0$ if $x = 0$, no?

anonymous · Answer

umm. yea

whpalmer4 · Answer

Umm, yeah, indeed.  So do any of the answer choices suggest a way where $x*y = 0$ even though $y \ne 0$?

anonymous · Answer

C ?

whpalmer4 · Answer

That would be my choice.  It shows a way that $x*y = 0$ could be true no matter what value $y$ has.  We're looking for a counterexample to the statement that $x*y = 0$ implies that $y=0$, and that is one.

whpalmer4 · Answer

It's like saying "all horses have 4 legs.  therefore, all animals with 4 legs are horses." to which you respond "a dog has 4 legs, and is not a horse."  That's your counterexample.

anonymous · Answer

lol (: thanks man

whpalmer4 · Answer

You bet!  Got any more? :-)

anonymous · Answer

Sadly, yes. i hate math. ill open a new question

whpalmer4 · Answer

Okay, operators are standing by to field your question :-)