Background Tutorials

• Understand the concept of a ratio and use ratio language to describe a ratio relationship between two quantities.

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    What's a Ratio?

    Ratios are everywhere! The scale on a map or blueprint is a ratio. Ingredients sometimes need to be mixed using ratios such as the ratio of water to cement mix when making cement. Watch this tutorial to learn about ratios. Then think of some ratios you've encountered before!

• Use similar triangles to explain why the slope m is the same between any two distinct points on a non-vertical line in the coordinate plane; derive the equation y = mx for a line through the origin and the equation y = mx + b for a line intercepting the vertical axis at b.

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    What are Similar Figures?

    Looking at two figures that are the same shape and have the same angle measurements? You have similar figures! Learn all about it in this tutorial!

• Understand that a two-dimensional figure is congruent to another if the second can be obtained from the first by a sequence of rotations, reflections, and translations; given two congruent figures, describe a sequence that exhibits the congruence between them.

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    What Does Congruent Mean?

    If two figures have the same size and shape, then they are congruent. The term congruent is often used to describe figures like this. In this tutorial, take a look at the term congruent!

• Given two figures, use the definition of similarity in terms of similarity transformations to decide if they are similar; explain using similarity transformations the meaning of similarity for triangles as the equality of all corresponding pairs of angles and the proportionality of all corresponding pairs of sides.

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    What are Corresponding Parts in Similar Figures?

    Identifying corresponding parts in similar figures isn't so bad, but you have to know what you're looking for. This tutorial does a great job of explaining the corresponding parts of similar figures! Take a look!