Definition of Similar Figures
Similar figures are figures that have the same shape but not necessarily the same size.
More About Similar Figures
- Any two corresponding sides in two similar figures have a common ratio called the scale factor.The trapezoids ABCD and EFGH shown above are similar. So,
- The ratio of areas of two similar figures is the square of the scale factor.
- The ratio of volumes of two similar figures is the cube of the scale factor.
Video Examples: Similar Figures and Proportions
Example of Similar Figures
Find the value of x, if the figures are similar.
Solved Example on Similar Figures
Ques: Find the number of Similar Figures in the measurement 4.07 cm.
Correct Answer: B
Step 1: Since the figures are similar, the ratios of the lengths of corresponding sides of the figures are equal.
Step 2: [Write the proportion.]
Step 3: [Substitute the values.]
Step 4: 12 × x = 5 × 6 [Write the cross products.]
Step 5: [Divide both sides by 12.]
Step 6: [Simplify.]
Step 7: [Convert improper fraction into mixed number.]
Step 8: The value of x is .