Unit 3 Similarity Review & Practice

Front

What is similarity in geometry?

Back

Similarity in geometry refers to the relationship between two shapes that have the same shape but may differ in size. The corresponding angles are equal, and the lengths of corresponding sides are proportional.

Front

What is a scale factor in dilation?

Back

A scale factor is a number that scales, or multiplies, the dimensions of a shape. In dilation, it determines how much larger or smaller the image will be compared to the original shape.

Front

If triangle ABC is dilated by a scale factor of 1/2, what happens to its area?

Back

The area of triangle ABC will be reduced to 1/4 of its original area because area scales by the square of the scale factor (1/2)^2 = 1/4.

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 two triangles are similar?

Back

Two triangles are similar if they satisfy one of the following criteria: AA (Angle-Angle) similarity, SSS (Side-Side-Side) similarity, or SAS (Side-Angle-Side) similarity.

Front

What does AA similarity mean?

Back

AA similarity means that if two angles of one triangle are equal to two angles of another triangle, then the triangles are similar.

Front

What does SSS similarity mean?

Back

SSS similarity means that if the lengths of the corresponding sides of two triangles are proportional, then the triangles are similar.

Front

What does SAS similarity mean?

Back

SAS similarity means that if two sides of one triangle are proportional to two sides of another triangle and the included angles are equal, then the triangles are similar.

Front

How do you find the length of a midsegment?

Back

To find the length of a midsegment, take the average of the lengths of the two sides it connects, or use the property that it is half the length of the third side.

Front

What is the effect of a dilation with a scale factor greater than 1?

Back

A dilation with a scale factor greater than 1 enlarges the shape, making it larger than the original.