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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.
Equilateral and isosceles triangles
1. Draw an isosceles triangle (a triangle that has two equal sides). Start out by drawing the two sides that have equal measure and draw the third side last. Use a ruler to make sure they are equal.
2. Make a guess about the angles in an equilateral triangle:
Then measure the angles in the equilateral triangles above. What do you notice?
ALL the angles are _______ degrees.
Based on that fact, draw an equilateral triangle. You can choose the length of the sides.
|An isosceles triangle has two angles that have the same measure.
They are called the base angles, The remaining angle is called the top angle.
4. a) Draw an isosceles triangle whose base angles are 40.
What is the top angle? The length of the sides can be any.
b) Draw an isosceles triangle whose base angles are 75. What is the top angle? Again the length of the sides can be any.
a) Is it possible to have an equilateral right triangle? Why?
If so, draw one.
b) Is it possible to have an equilateral obtuse triangle? Why? If so, draw one.
f) Is it possible to have an isosceles acute triangle? Why? If so, draw one.
7. Calculate the angles. Don't measure, because the pictures are not exact. Note especially if the triangle(s) are equilateral or isosceles.
[Pictures available in the ebook]
New terms to remember: