The support arm, AB, is
perpendicular to a line tangent to this curve on a roller coaster at the point of tangency B.

The equation of the tangent line to the curve at B is 3x + 2y = 28.

Find the equation of the support arm, AB.
B(4,8)

Lines perpendicular to tangents to curves, at
the point of tangency, are referred to as “normals.”