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# ->, <->, <- notation q Watch

1. A: If x = 3
B: x^2 = 9
write ->, <->, or <-, linking the statements.

I don't understand why it isn't <-> because if x is 3 then obviously 3 squared is 9. It also works the other way because if x^2 = 9 then ONLY 3 could be the x value, nothing else squared gives 9. Why is the answer -> and not <->?
2. (Original post by Magenta96)
if x^2 = 9 then ONLY 3 could be the x value, nothing else squared gives 9.
Oh come on really?
3. (Original post by Magenta96)
A: If x = 3
B: x^2 = 9
write ->, <->, or <-, linking the statements.

I don't understand why it isn't <-> because if x is 3 then obviously 3 squared is 9. It also works the other way because if x^2 = 9 then ONLY 3 could be the x value, nothing else squared gives 9. Why is the answer -> and not <->?

means "if and only if".

Note that
4. (Original post by Mr M)
Oh come on really?
PRSOM!
5. (Original post by Mr M)
Oh come on really?
OH, I had a blank moment and completely forgot about -3 x -3 lol, sorry
6. (Original post by Magenta96)
OH, I had a blank moment and completely forgot about -3 x -3 lol, sorry

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