Introduction to equations with two variables - 6th grade math
This lesson is an introduction to equations containing two variables, such as y = 2x. In the first example, I make a table of x and y values based on the equation y = 2x, and then the plot the points from it, producing a graph of the equation.
Then we look at the same situation in reverse: a table of x and y values is given, and we need to write the equation and make a graph.
In the 2nd part of this lesson (below), we use two variables to describe some real-life situations. We look at two common real-life situations, and find two variables in each that change in relationship to one another. Then, we write an equation relating the two variables. Then we use a table to write down some values for the variables from the equation, and lastly plot those points to make a graph.
The first situation says that one light bulb costs $4. We consider the two variables: the number of light bulbs and the cost.
In the other situation, you bicycle at the speed of 15 km/h. In this case, the two variables are time and distance.
See also
Write expressions from word phrases — video lesson
Math Mammoth Grade 6 curriculum