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📐 Mathematics  ·  Straight Lines  ·  JEE

The eccentricity of ellipse 4x² + 9y² = 36 is:

Answer: √5/3.

  • A √5/3
  • B 2/3
  • C 1/3
  • D √7/3

Correct answer: A. √5/3

Explanation: Divide by 36: x²/9 + y²/4 = 1. So a²=9, b²=4 (a>b, major axis along x). c²=a²−b²=9−4=5. Eccentricity e=c/a=√5/3. Ans: √5/3.

Slope as Rise over Runxy(x₁,y₁)(x₂,y₂)run = x₂−x₁rise = y₂−y₁m = rise/run = (y₂−y₁)/(x₂−x₁) = tanθ

The slope of a line is the ratio of vertical change (rise) to horizontal change (run) between any two points on it - equivalently, the tangent of the angle θ the line makes with the positive x-axis.

Concept context

Points, lines, and curves on the Cartesian plane

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