Better Lesson
Better Lesson: More Than Two Numbers
The big idea of this lesson is that three (or more) numbers can be grouped together and added. The order of this grouping doesn't matter.
Purple Math
Purplemath: Complex Numbers: Introduction
This website provides an in-depth lesson on complex numbers. You learn about simplifying, adding, and multiplying complex numbers by viewing example problems that are worked through step-by-step. Continue on to pages 2 and 3 which...
Illustrative Mathematics
Illustrative Mathematics: N Rn Sums of Rational and Irrational Numbers
The goal of this task is to examine sums and products of rational and irrational numbers. One important property of rational numbers is that their decimals always terminate or repeat: using a slightly different formulation, a rational...
Khan Academy
Khan Academy: Add and Subtract Fractions Word Problems
Practice solving fraction addition and subtraction word problems. The fractions in these problems have unlike denominators. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or...