If the point (x,sqrt3/3) is on the unit circle, what is x?

2/3
sqrt6/3
4/9
sqrt2/3

Those are my options, but I'd like an explanation too. I looked at the guild, and it was too wordy, so if someone wouldn't mind helping me with this.

Question

If the point (x,sqrt3/3) is on the unit circle, what is x?

2/3
sqrt6/3
4/9
sqrt2/3

Those are my options, but I'd like an explanation too. I looked at the guild, and it was too wordy, so if someone wouldn't mind helping me with this.

anonymous · Answer

@Mertsj , do you have anyone who could explain or do you know?

mertsj · Answer

Use the Pythagorean Theorem.  The hypotenuse is 1 because you are on the unit circle.  One leg is x and the other leg is sqrt3/3

anonymous · Answer

I'm thinking I have to use my options as x, and solve them to see if they equal to a while.

anonymous · Answer

whole*

mertsj · Answer

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anonymous · Answer

@Mertsj , I've plugged all of the options in and they give me all decimals no wholes, what am I doing wrong? I'm using the theorem you gave me too.

mertsj · Answer

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