Similar Shapes and Scale Drawings 7.5C

Front

What does it mean for two shapes to be similar?

Back

Two shapes are similar if they have the same shape but may differ in size. Their corresponding angles are equal, and their corresponding sides are in proportion.

Front

What is a scale drawing?

Back

A scale drawing is a representation of an object that is proportional to its actual size. It uses a specific ratio to show the relationship between the dimensions of the drawing and the real object.

Front

If a scale is 1 cm : 5 m, how would you convert 15 m to centimeters in a scale drawing?

Back

To convert 15 m to centimeters, multiply by 100 (since 1 m = 100 cm). 15 m = 1500 cm. Then, using the scale, 1500 cm would be represented as 1500 cm / 5 = 300 cm in the drawing.

Front

What is the formula to find the length of a side in a similar triangle?

Back

If triangle ABC is similar to triangle DEF, then the ratio of the lengths of corresponding sides is equal. If AB/DE = AC/DF = BC/EF, you can use this ratio to find unknown lengths.

Front

How do you find the actual length of an object using a scale?

Back

To find the actual length, multiply the length on the scale drawing by the scale factor. For example, if the scale is 1 cm : 10 m and the drawing shows 5 cm, the actual length is 5 cm * 10 m/cm = 50 m.

Front

What is the relationship between corresponding angles in similar shapes?

Back

In similar shapes, corresponding angles are equal. This means that if two shapes are similar, each angle in one shape has a matching angle in the other shape that is the same measure.

Front

If triangle RST is similar to triangle RVW and the length of side RS is 6 cm and side RV is 9 cm, what is the ratio of their corresponding sides?

Back

The ratio of the corresponding sides RS to RV is 6 cm : 9 cm, which simplifies to 2 : 3.

Front

What is the scale factor?

Back

The scale factor is the ratio of the lengths of two corresponding sides of similar shapes. It indicates how much larger or smaller one shape is compared to the other.

Front

How do you calculate the length of a side in a scale drawing if the actual length is known?

Back

To calculate the length of a side in a scale drawing, divide the actual length by the scale factor. For example, if the actual length is 20 m and the scale is 1 cm : 4 m, the length in the drawing is 20 m / 4 m/cm = 5 cm.

Front

What is the purpose of using scale drawings in real life?

Back

Scale drawings are used in various fields such as architecture, engineering, and cartography to represent large objects or areas in a manageable size while maintaining accurate proportions.