Similar Figures & Scale Drawings

Front

What are similar figures?

Back

Similar figures are shapes that have the same shape but may have different sizes. Their corresponding angles are equal, and their corresponding sides are proportional.

Front

What does it mean for sides to be proportional?

Back

Sides are proportional when the ratios of the lengths of corresponding sides of two figures are equal.

Front

How can you determine if two triangles are similar?

Back

Two triangles are similar if they have two corresponding angles that are equal (AA criterion) or if the sides are in proportion (SSS or SAS criteria).

Front

What is a scale drawing?

Back

A scale drawing is a representation of an object or a figure that is proportional to the actual size, using a specific ratio or scale.

Front

If a scale drawing has a scale of 1:4, what does this mean?

Back

A scale of 1:4 means that 1 unit on the drawing represents 4 units in real life.

Front

What is the relationship between corresponding angles in similar figures?

Back

In similar figures, corresponding angles are equal.

Front

How do you find the scale factor between two similar figures?

Back

The scale factor is found by dividing the length of a side of one figure by the length of the corresponding side of the other figure.

Front

If two similar rectangles have a scale factor of 2:3, what does this imply about their areas?

Back

The area of the larger rectangle is (2/3)² = 4/9 times the area of the smaller rectangle.

Front

What is the formula for the area of similar figures?

Back

If the scale factor between two similar figures is a:b, then the ratio of their areas is a²:b².

Front

Can two figures be similar if they have different shapes?

Back

No, two figures cannot be similar if they have different shapes; they must have the same shape.