Curated OER
Addition Principle
In this addition principle learning exercise, 8th graders solve 20 different problems that include applying the addition principle to each equation. First, they solve each of the listed equations. Then, students determine the value of...
CK-12 Foundation
Ck 12: Probability: Tree Diagrams Grades 9 10
[Free Registration/Login may be required to access all resource tools.] Use tree diagrams to solve for probabilities.
Help Algebra
Help algebra.com: Addition Principle
Beginning with a discussion of equivalent equation, this site describes the Addition Principle and how it is used to help solve algebraic equations.