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A.1: Similar Triangles

  • Page ID
    91817
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    Two triangles \(T_1,T_2\) are similar when

    • (AAA — angle angle angle) The angles of \(T_1\) are the same as the angles of \(T_2\text{.}\)
    • (SSS — side side side) The ratios of the side lengths are the same. That is

      \begin{align*} \frac{A}{a} &= \frac{B}{b} = \frac{C}{c} \end{align*}

    • (SAS — side angle side) Two sides have lengths in the same ratio and the angle between them is the same. For example

      \begin{align*} \frac{A}{a} &= \frac{C}{c} \text{ and angle $\beta$ is same} \end{align*}


    This page titled A.1: Similar Triangles is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Joel Feldman, Andrew Rechnitzer and Elyse Yeager via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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