Solving Equations: Summary: Solving Equations
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...
Solving Equations: Using An Equation to Solve a Word Problem
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...
Solving Equations: Unknowns, Coefficients and Constants
This clip introduces the terms "unknowns," "constants" and "coefficients," and explains the role each plays in a word problem.
Solving Equations: Introducing Equations
This clip introduces a type of number sentence known as an equation, which the clip describes as "a kind of balance scale" having two parts connected by an equal sign.
Ratio and Proportion: Simplifying the Comparing of Fractions by Cross Multiplying
This clip explains that cross multiplying is a shortcut which allows us to determine if two fractions are the same. The fractions are compared by multiplying the numerator of each by the denominator of the other. If the products are the same, then t...
Ratio and Proportion: Problem In Which The Denominator Is Missing, A
This clip explains that, whether it's a numerator or a denominator that's missing, in order to be sure that "
we really have a proportion...the cross products must be equal."
Ratio and Proportion: Solving Word Problems Involving Proportions
This clip presents two word problems involving proportions which require dividing both sides of an equation by the same number. The answers are checked by forming cross products which are equal.
Word Problems: Two-Step Problem, A
This clip introduces the use of parentheses in two-step problems, explaining that the first step is always to solve the problem inside the parentheses, and then use that answer to solve the main problem.
Word Problems: Turning Word Problems Into Number Sentences
This clip explains that students who have no trouble with ordinary arithmetic sometimes get confused by word problems. The clip then suggests ways to solve word problems by breaking them down into a series of steps.