Question

How do you find the equations for the normal line to `x^2+y^2=25` through (4,3)?

Answer 1

`y=3/4x`

Explanation:

This is the equation of a circle with center in the origin and `R=5`.

For the properties of the circle, the radius is normal to the tangent, so the normal line will pass through `(0,0)` as well as through `(4,3)` and its equation is given by:

`y=3/4x`