Windows 7: School help

So, I just got silently disappointed today at school. In our geometry class, I was asked the question by my teacher: True or false, all chords of a circle contain exactly 2 points. So, I answered: false. My reason (I didn't point this out): Well, the center of a circle is a part of the circle, if a line intersects an existing point (the center of the circle in the current case), then it contains the point (i might be wrong), and a diameter is a chord. So, my mind told me to answer False since the diameter is a chord, and it intersects the center of a circle, thus containing it. My teacher had that scary look at me, and began to incorrectly explain to me that a chord contains two points. I am a very inconfident student, I only speak when I'm mad. She began to tell the class about people who think they're always right that was very sarcastic on my view.That moment, my teacher was clearly behaving unprofessionally. She even told me that I cannot accept what is said to be right. I was supposed to tell her that I am a person that believes logically, you can't just tell me something is right and that's it, you have to explain a reason. But then she continued and had that unwelcoming face. She clearly was influencing close-mindness to students, overprioritizing discipline. Anyways, even though I could be wrong, her treatment to students is clearly biased and incorrect. I just want to leave to you guys whether my answer was right or wrong, since I've just lost trust from my teacher.

Doesn't anyone care for change? Education is Important! We deserve a decent education! I have much to say, but are usually useless to say. Who cares about the future? Teachers are pure idiots, they don't purely do their jobs, they apparently don't value correctly education. youtube.com/watch?v=zDZFcDGpL4U
Can anyone help me with my question, because I'm filing a complain against that teacher?

In Geometry, all chords of a circle have exactly 2 points. A point is defined as being the position on the circumference of the circle where the line of the chord passes through. A chord that passes through the centre of a circle is its diameter.

See Chord (geometry) - Wikipedia, the free encyclopedia

http://en.wikipedia.org/wiki/Chord_(geometry)

Red highlight above added by me.
Google is our friend.

Google search box typed in > chords of a circle.
chords of a circle - Google Search

Bested by Dwarf.

Chord may or may not pass through the center of the circle so your argument is wrong.

You're wrong, the teacher's right.

The center point of a circle isn't part of the circle. A circle is only the line.

Guess it's time to make your peace with your teacher.

In Geometry, all chords of a circle have exactly 2 points. A point is defined as being the position on the circumference of the circle where the line of the chord passes through. A chord that passes through the centre of a circle is its diameter.

A diameter is a chord, it is the longest chord, it has the definition of a chord. Therefore the diameter which meets 3 points and contains them, is included in the statement "every chord".

A line segment is a series of points, not just two endpoints. The center exists, because it is necessary for the definition of the radius, therefore FALSE.

In Geometry, a point is defined as being where 2 or more lines intersect, or where a single line changes direction. For a chord and a circle, the intersection points are where the line passes through the circle, the intersecting line being that which forms the circumference of the circle. Even the diameter, or the Great Chord, holds true to this definition. Whilst it is true that the diameter passes through the centre of the circle, it still has only 2 points because, apart from its intersections with the circumference, there are no other intersections which will define a point.

Well whatever the answer is, your teacher was still being unprofessional about it all.