Math Planet
Math Planet: Pre Algebra: Measure Areas
Demonstrates how to calculate the area of two-dimensional shapes using formulas. Covers parallelogram, triangle, trapezoid, and circle. Includes a video modeling how to find the area of a circle and a triangle. [0:59]
Khan Academy
Khan Academy: Algebra Ii: Manipulate Formulas
Manipulate multi-variable formulas to isolate specific variables in order to solve some word problems. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
Math Planet
Math Planet: Algebra 1: Radical Expressions: The Distance and Midpoint Formulas
Distance and midpoint formulas are explained through the use of examples and a video lesson. [1:58]
Mathigon
Mathigon: Algebra: Fibonacci Numbers
This lesson focuses on Fibonacci numbers, a pattern based on the sum of the two previous numbers. It offers examples and practice exercises using some form of Fibonacci numbers.
Purple Math
Purplemath: Solving Polynomials: How To
Demonstrates the steps involved in solving a general polynomial, including how to use the Rational Roots Test and synthetic division. Points out when using a graphing calculator can be very helpful.
Purple Math
Purplemath: Special Factoring: Differences of Squares
Demonstrates how to use the formula for finding the differences of squares, and warns against trying to factor a sum of squares.
Cool Math
Coolmath: Perpendicular Lines
This CoolMath Resource will help students determine if lines are perpendicular by finding the slope, using the point-slope formula, and graphing.