Chapter 7 Test

Ratio

Compares 2 numbers by division. Written as A to B, A:B, and A/B.

Proportion

Equation taking 2 ratios who are equal

Similar

Figures that have the same shape, but not necessarily the same size

Similar polygons

Two polygons with congruent corresponding angles and their corresponding side lengths are proportional

Similarity Ratio

The ratio of the lengths of the corresponding sides of two similar polygons

Angle-Angle Similarity

If two angles of one triangle are congruent to the two angles of another triangle, then the triangles are similar.

Side-Side-Side Similarity

If three sides of one triangle are proportional to three sides of another triangle, then the triangles are similar.

Side-Angle-Side Similarity

If two sides of one triangle are proportional to two sides of another triangle and their included angles are congruent, then the triangles are similar.

Triangle Proportionality Theorem

If a line parallel to a side of a triangle intersects the other two sides, then it divides those sides proportionally.

Triangle Proportionality Converse

If a line divides two sides of a triangle proportionally, then it is parallel to the thirds side.

Two-Transversal Proportionality

If three or more parallel lines intersect two transversals then they divide the transversals proportionally.

Triangle Angle Bisector Theorem

An angle bisector of a triangle divides the opposite side into two segments whose lengths are proportional to the lengths of the other two sides.

Indirect measurements

Any method that uses formulas, similar figures, and/or proportions to measure an object

Scale drawing

Represents an object as smaller than or larger than its actual size

Scale

The ratio of any lengths in the drawing to the corresponding actual length

Dilation

A transformation that changes the size of a figure but not its shape

Preimage

Original figure, can be reduction or enlargement, the preimage and image are always similar

Scale factor

Describes how much the figure is enlarged or reduced