Question Detail
Question
Find the equation of the tangent to the circle x² + y² = 10 at the point (4, -2).
Correct Answer
Option D is the correct answer.
Detailed Explanation
Substituting into xx₁ + yy₁ = a² gives 4x + (-2)y = 10, which simplifies to 4x - 2y = 10. Dividing by 2 gives 2x - y = 5. So both 4x - 2y = 10 and 2x - y = 5 represent the same line.
Hint
Use the formula xx₁ + yy₁ = a², where x₁=4, y₁=-2, and a²=10.