pAIrmatic Lessons

Similar Figures

Grade 7 Grade 8 Geometry

GeometryAngles and Polygons Triangle Formulas Pythagorean Theorem and Special Right TrianglesSimilar FiguresArea of Quadrilaterals and Polygons Circles Volume and Surface Area Transformations

Scale factor k

Matching sides

\frac{A B}{D E} = \frac{B C}{E F} = \frac{C A}{F D} = k

Perimeters

ratio k

Areas

ratio k^{2}

Volumes of similar solids

ratio k^{3}

Triangle theorems

Angle bisector theorem

\frac{A D}{D B} = \frac{A C}{B C}

CD bisects angle C

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