Alg1 Lesson 1.2: Recognizing Direct Variation

Important Info:
A linear relationship has a constant rate of change, which can be visualized as the slope of the associated graph.
A linear direct variation can be expressed in the algebraic form y = kx, where k is a non-zero constant.

Measure each square side and diagonal in millimeters (one tic mark on cm side).

1.2a: Use a ruler

Write a rule to determine the length of the diagonal based on the length of the side.

Sketch a Graph

For the side lengths and the corresponding diagonal lengths.

Create a Table of Values

Share your table, graph, and rule with a partner.

Come up with a formal algebraic rule to represent the relation between a square's side and diagonal lengths.

Pythagorean Thm

The measure of one quantity can be thought of as a multiple of the other.

Reasoning

How can we tell that each of these represents direct variation?

Look back at your table, graph, and formula for the square lengths

How can you determine whether the temperature in degrees Celsius and the temperature in degrees Fahrenheit vary directly?

It is known that 0ºC is 32ºF and 100ºC is 212ºF.
It is encouraged to construct a table and/or graph.
Use the following words when explaining: constant of proportionality, input, output, and direct variation.

In Your Journal...

Fill out the graphic organizer in your journal for direct variation.

Choose a skill TEKS to focus on, get that foldable and 1 WS from the folders on wall. Go to Canvas to click skill links.

Look at Calendar Paper

Share your thoughts with others around you!

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