A new guideline for simplifying radicals is introduced: the terms in a fully-simplified radical expression must have no common radical factors. Simplifying a radical expression by adding or subtracting common radical factors is illustrated.
The process of simplifying to find a common radical factor is demonstrated.
This clip summarizes signed fractions. It explains that negative fractions are just as useful as any other kind of negative number. The clip then re-visits the question of what exactly constitutes a negative fraction. It states that, if the numerato...
This clip provides a subtracting signed fractions problem in which negative 3/5 is subtracted from 4/5. The clip advises the student to "
change the sign of the subtrahend and change the subtraction to addition. The problem become 4/5 plus positive...
This clip explains that we work with decimal fractions because, "
our way of writing numbers depends on the number ten, so sticking with powers of 10 makes the arithmetic very easy."
This clip summarizes how to solve equations. It describes the relationship between word problems, number sentences and equations, noting that the latter are, "
nothing more than a statement that two mathematical expressions are equal." The clip rev...
This clip describes the steps in solving a simple equation. It states that "...the important thing is to study the equation, decide what you want to move around or get rid of, and proceed step by step." It also advises that "
it's usually easiest t...
This clip explains that, "
what makes equations tricky is that there's no set rule for doing them all. You have to size up each one separately, decide what needs doing, and get it done." The clip then goes through an equation step by step, beginnin...
This clip demonstrates how to solve an equation involving subtraction, X-9=7, which eventually comes out to be X=7+9, or 16.
This clip uses the number line to illustrate that there can be negative numbers as well as positive numbers. Negative numbers on the number line are located to the left of the zero, rather than to the right.