Question

Answer the following :

Find the equation of tangent to Circle x² + y² = 5, at the point (1, –2) on it

Answer 1

Equation of the tangent to the circle

x² + y² = r² at (x₁, y₁) is xx₁ + yy₁ = r²

∴ equation of the tangent to the circle x² + y² = 5 at (1, –2) is

x(1) + y(– 2) = 5

i.e., x – 2y = 5.