The position vectors of A and B are (2, 3) and (8, 11). What is the length of AB?
Answer and explanation
Correct answer: D. 10
- Step 1: AB = (8 - 2, 11 - 3) = (6, 8). Step 2. Length = root(36 + 64) = root 100 = 10. Answer: 10. Why not the others: 14: That adds the two differences. 100: That is the length squared. 2: That is the difference between the differences.
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