Verifying Similar Figures
Two figures are similar if they have the exact same shape and their corresponding sides are proportional. The corresponding side lengths of the two figures are related by a scale factor.
A scale factor is the constant number you can multiply any side length in one figure by to find the corresponding side length of the similar figure.
Figure A
3 yd.5 yd.
Figure B
12 yd.20 yd.
In this problem, you will verify that the two rectangles are similar and find the scale factor from each figure to the other. Since rectangles have two sets of equal parallel sides, we will only need to find the ratios for two sets of sides; the horizontal and vertical lengths. If these ratios are equal, the rectangles are similar.

Note: In some cases, the simplified and unsimplifed ratios may be equal.
Find the ratio: Vertical Side Length Figure AVertical Side Length Figure B\displaystyle \frac{\text{Vertical Side Length Figure A}}{\text{Vertical Side Length Figure B}} Unsimplified:  

Simplified:  
Find the ratio: Horizontal Side Length Figure AHorizontal Side Length Figure B\displaystyle \frac{\text{Horizontal Side Length Figure A}}{\text{Horizontal Side Length Figure B}} Unsimplified:  

Simplified:  
Find the ratio: Vertical Side Length Figure BVertical Side Length Figure A\displaystyle \frac{\text{Vertical Side Length Figure B}}{\text{Vertical Side Length Figure A}} Unsimplified:  

Simplified:  
Find the ratio: Horizontal Side Length Figure BHorizontal Side Length Figure A\displaystyle \frac{\text{Horizontal Side Length Figure B}}{\text{Horizontal Side Length Figure A}} Unsimplified:  

Simplified:  
To scale Figure A to the size of Figure B, multiply the length of each side of Figure A by the scale factor of  
To scale Figure B to the size of Figure A, multiply the length of each side of Figure B by the scale factor of