Find the eccentricity of the ellipse x²/25 + y²/9 = 1.
Answer and explanation
Correct answer: A.
- Step 1: Here a² = 25 and b² = 9, so c² = a² − b² = 16, c = 4. Step 2. e = c/a = 4/5. **Answer: . Why not the others:** is what you get if you use b/a. is what you get if you use c/b. is what you get if you give e².
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