Definition of a 306090 triangle along with the ratio of its sides.
Math Open Reference

In this Early Edge video lesson, you'll learn more about Triangles: Perimeter and Area, so you can be successful when you take on highschool Math & Geometry.
The Princeton Review

In this Early Edge video lesson, you'll learn more about Complementary and Supplementary Angles, so you can be successful when you take on highschool Math & Geometry.
The Princeton Review

In this Early Edge video lesson, you'll learn more about Types of Angles, so you can be successful when you take on highschool Math & Geometry.
The Princeton Review

Definition and properties of right triangles
Math Open Reference

Calculate the perimeter and area for each triangle. Answers included.
MathDrills.com

This website will help you with squares and their properties. Such as side length, diagonal length, area and perimeter.
WebMath

This page will allow you to calculate things related to a right triangle. Such as the base, the height, area, perimeter, and Pythagorean Thm.
WebMath

The worksheets below can be used as part of extra math homework. These geometry worksheets are free and easily printable. They cover typical school work from grade 4 through 8. They include questions on polygons, 3D objects, angles, and calculations of area, volume, etc.
Helping With Math.com

Definition and picture of a 3:4:5 triangle. Gives other examples of pythagorean triplets.
Math Open Reference
