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Maria's Math news - a FREE math newsletter for parents and teachers
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Various worksheets on TONS of math topics you can generate for free!
Basic operations worksheet generator is updated! Make worksheets for whole numbers or integers - all four operations, including add & subtract or multiply & divide - horizontal or vertical - add a border and/or extra workspace, use a variable, and more.
Advice, reviews, and resources to help you choose a math curriculum!
Online math games, tutorials, and activities
Games you can play online, interactive tutorials, fun math websites and more. Arranged by topic/level for ease of use.
Learn how to TEACH concepts or about general concerns in math education.
In-depth reviews of math products
Math help & tutoring
A list of free message boards, math help websites, and online tutoring services.
Fun and games
I have two games on my site, plus links to many.
Game: Choose Math Operation
Word guess game (easy hangman)
Word guess game (difficult)
The ideas in this geometry lesson are taken from the Geometry ebook that I sell at MathMammoth.com. This lesson plan does not contain all the problems the Geometry ebook does.
Angles of a triangle
|In the previous study you probably made a guess that the sum of the
angles in a triangle is 180. That is true. Here is a proof for it. Look at the picture.
1. Calculate the angle marked with the question mark. Note: do not measure since the pictures are not exact. What principles should you use?
[Pictures available in the ebook]
2. Draw a triangle whose all three angles have the same measure. What is that measure?
3. Try to draw a triangle that has two right angles. Can you do it? Why?
6. Draw a triangle whose one angle is 35 and another angle is 85. Can you draw the triangle without calculating the measure of the third angle?
Calculate (do not measure) the angle marked with ?.