Polygons and Triangle Similarity Flashcard

Front

What is a midsegment in a triangle?

Back

A midsegment is a line segment that connects the midpoints of two sides of a triangle. It is parallel to the third side and its length is half the length of that side.

Front

How do you determine if a figure is a polygon?

Back

A figure is a polygon if it is a closed plane figure formed by three or more line segments that do not intersect except at their endpoints.

Front

What is the sum of the interior angles of a polygon with n sides?

Back

The sum of the interior angles of a polygon with n sides is given by the formula (n-2) × 180°.

Front

What is the definition of a convex polygon?

Back

A convex polygon is a polygon where all interior angles are less than 180°, and no line segment between any two points on the boundary ever goes outside the polygon.

Front

What is the definition of a concave polygon?

Back

A concave polygon is a polygon that has at least one interior angle greater than 180°, causing at least one line segment between two points on the boundary to lie outside the polygon.

Front

How do you find the measure of an interior angle of a regular polygon?

Back

To find the measure of an interior angle of a regular polygon, use the formula: (n-2) × 180° / n, where n is the number of sides.

Front

What is triangle similarity?

Back

Triangle similarity means that two triangles have the same shape but may differ in size. Their corresponding angles are equal, and their corresponding sides are in proportion.

Front

What is the relationship between the angles of similar triangles?

Back

In similar triangles, corresponding angles are equal, and the ratios of the lengths of corresponding sides are equal.

Front

What is the exterior angle theorem?

Back

The exterior angle theorem states that the measure of an exterior angle of a triangle is equal to the sum of the measures of the two non-adjacent interior angles.

Front

How do you determine the number of sides of a regular polygon given an interior angle?

Back

To find the number of sides (n) of a regular polygon given an interior angle (A), use the formula: n = 360° / (180° - A).