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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 Math Mammoth Geometry 1 book.
Area of right triangle
|In the following pictures the rectangle is divided up into two right
The thus formed two right triangles are identical in the sense that if you could
move them on top of each other, they would exactly match.
|Let us look closer at the last triangle in the previous paragraph. Hopefully you figured out that its area is 12. To confirm that we can actually count the little squares in the triangle. Note that some parts don't form a whole square, but combining them we get whole squares and can then count them.|
|[picture omitted from Free lesson plan; available in the ebook]|
|1. Find out the area of the following right triangles.|
|2. Here you see two different shaped
right triangles that both have the area of 10:
In each case draw 3 different
right triangles that