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Geometry: Similarity and Proportion Classroom ActivitiesDownload
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Constructing Similar Triangles

Students investigate three different methods of constructing similar triangles.
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Midsegments of Triangles

Students explore the properties of the midsegment, a segment that connects the midpoints of two sides of a triangle.
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    TI-84 Plus CE
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    TI-84 Plus C Silver Edition
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Ratios of Similar Figures

Students will explore the ratio of perimeter, area, surface area, and volume of similar figures in two-dimensional figures.
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    TI-84 Plus CE
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    TI-84 Plus C Silver Edition
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Side-Splitter Theorem

Students explore the side-splitter theorem by collecting data from a triangle with a line parallel to one of its sides.
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    TI-84 Plus C Silver Edition
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Similar or Congruent?

In this activity, students will explore AAA and SSS relationships in triangles to support understanding of the concepts of triangle similarity and congruence.
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    TI-84 Plus CE
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    TI-84 Plus C Silver Edition
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The Geometric Mean

In this activity, students will establish that several triangles are similar and then determine that the altitude to the hypotenuse of a right triangle is the geometric mean between the segments into which it divides the hypotenuse.
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    TI-84 Plus CE
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    TI-84 Plus C Silver Edition
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Ratios of Similar Triangles

In this activity, students will explore two ways of comparing side lengths of similar triangles. They will calculate ratios and change the triangles to see how the ratio changes. Then they will write proportions using the ratios.
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    Congruent or Not?

    In this activity, students will investigate whether AAA, SAS, ASA, or SSA relationship guarantee that two triangles are congruent or not. This is an exploratory activity where students will need to know how to change between pages, grab and move points, and measure lengths.
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