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About Azeem Hussain
Expertise
I can answer virtually any kind of question dealing with of Math 536 and below, my forte being in parabolic functions and analytical geometry. I'm currently learning Linear Algebra, and cannot answer questions that deal with subject matter more advanced than that.

Experience
I am neither a professor nor a teacher of this subject. I am merely a student who is gifted at mathematics and enjoys being of service to his community. I frequently tutor people in math and the results are usually great.

Publications
Reflections, Riverside School Board (2005, 2006)

Education/Credentials
Diploma of Secondary Studies from Chambly Academy High School, and IBO-MYP certificate as well. My lowest mark on a high school math final was 97%, peaking at 99% in 2006 and 2007 (second-highest Math 436 mark in the province). Being a Quebecer, I am fluent in English and French and can respond to questions easily in both languages.

Awards and Honors
Pascal Math Competition, School Champion(2007)

 
   

You are here:  Experts > Science > Math for Kids > Geometry > Non-collinear Points

Geometry - Non-collinear Points


Expert: Azeem Hussain - 3/1/2009

Question
I am having trouble with this question:
Plot 7 non-collinear points on a page. How many different triangles can be formed by joining three of the points at a time.
I also don't get 'at a time'. What does it mean?
Thank you.

Answer
Hey Mia!

Ignore the "at a time" part.  To make a triangle you need to join three points, and that's all that's saying.

Make 7 random points on a page.  Now make as many different triangles as you can.  There are quite a few.  If you're doing this systematically, you will find yourself drawing the same ones two or three times over.

The correct number may be found by using a statistics procedure.  There are three elements (points to join).  The formula would be (n)(n-1)(n-2)/3, where n is the starting number (7 in this case).

I get 70 triangles using this method.

Thanks for asking,
Azeem

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