A-LEVEL MATHEMATICS Topic : Coordinate Geometry - Triangles and Normals

Diagram not to scale

Typically in coordinate geometry we are concerned with lines and normals, distances and circles.
We may be of, for the above diagram:
a)Show that AC is perpendicular to AB.
b)Find the distance AB.
a) Gradient of
Gradient of
The product of the gradients is -1 so AC and AB are at right angles.
b)