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Word Problems

Browse Middle School Two-Dimensional Geometry
Stars indicate particularly interesting answers or good places to begin browsing.

Selected answers to common questions:
    Classifying quadrilaterals.
    Pythagorean theorem proofs.

Transversal - Meaning and Examples [11/14/1994]
I have a 7th grade student who would like to know the meaning and examples of "transversal".

A Triangle with Three Right Angles [12/01/1999]
How can you make a triangle with three right angles?

Trisecting a Line [11/03/1997]
How would you trisect a line using a compass and a straight edge?

Trisecting a Line [01/30/1998]
How do I trisect a line using only a straightedge and compass?

Trisecting a Line Segment [08/13/1999]
How can I measure one-third of a line of an unknown length using a compass and a straightedge?

Trisecting an Angle [4/16/1996]
I can bisect an angle easily but I can't trisect it perfectly. Would you please send me instructions?

Trisecting Angles [5/30/1995]
Can an angle be trisected?

Trisecting a Right Angle [12/16/1996]
An explanation of how to trisect a 90 degree angle, plus some constructions.

Two Column Proof of a Theorem [08/12/1998]
Write a two-column proof and give numbered statements with reasons....

The Unknown Angle that Didn't Matter [10/01/2014]
A geometry word problem leads to the confounding result 120° equals 0. Doctor Ian takes a closer look at how to interpret this puzzle's statement — and empty solution sets generally.

Using a Protractor [8/15/1996]
How do I measure angles using a protractor?

Vertical Angle [11/15/2001]
What are vertical angles? Are they equal?

Vertical Angles [10/27/1996]
What are vertical angles?

What Are Proofs? [08/12/1997]
I am homeschooling and do not understand proofs. Can you help me out?

What is a Jordan Curve? [06/07/2006]
What is a simple definition of a Jordan curve I can give my 5th graders?

What is a point? [8/26/1996]
Define a point, please.

What Is a Theorem and Why Are They Important? [08/15/1997]
I don't understand how theorems help us learn.

What is a Vertex? [12/06/2001]
And what does vertices mean?

What is Dimensional Analysis? [11/26/2001]
What is dimensional analysis and how does it work?

What is Geometry For? [03/01/2002]
What is geometry really for?

When Does 2D Become 3D? [01/20/2003]
Is a piece of paper a 3D object when held up in space? Or is it a 2D object in 3D space?

When is the expression Q.E.D. used? [02/15/1999]
More on Q.E.D.

Why Cubed? [11/27/2001]
Why do we use "cubed" for the volume of a figure?

Why is K Used as an Abbreviation for Area? [11/29/2004]
Many textbooks use the letter K to represent area in formulas, instead of A. Do you know why that is?

Why Proofs? Definitions and Axioms [09/16/2001]
Why are proofs important in the development of a mathematical system like geometry?

Why Study Tangrams? [10/27/1999]
How can a person use tangrams in the real world?

World War II Window Blackout [10/21/2001]
Mr. Brown had a square window 120cm x 120cm, but the only material he could find was a sheet of plywood 160cm x 90cm; same area, different shape. He drew some lines and cut out just two congruent shapes, which he joined to make a square of the correct size. How did he do it?

Zero Degree and 360 Degree Angles [10/22/2003]
I am curious if there is such a thing as a zero degree angle, and if so, what does it look like? I am also wondering if a zero degree angle equals a 360 degree angle? I understand that a 360 degree angle is essentially a circle, or the amount of 'turn' that equals a circle. I am pondering how you would draw a 360 degree angle?

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