What you’ll learn
Use SSS similarity.
Key idea
SSS similarity requires the same image/original ratio for all three corresponding pairs.
Every corresponding side ratio is required; two proportional pairs are insufficient for SSS.
Worked example
Enter the exact value or ordered values in the format requested below.
Corresponding original sides (12, 16, 20); first two image sides 6,8. Third image side 10. Find the forward scale factor, verifying SSS ratios.
- First two ratios agree at 1/2.
- Third side must be 20 times 1/2=10; all three ratios then match.
Answer: 1/2
Quick Check
Evaluate a worked attempt at use sss similarity, identify the first invalid step, and provide the correction.
Corresponding original sides (9, 12, 15); first two image sides 9/2,6. Third image side 8. Student Step 1 checks the first two ratios 1/2. Step 2 concludes SSS similarity without checking the third. Find first invalid step and correct.