MathDB

Two distinct circles

K_1

and

K_2

are drawn in the plane. They intersect at points

A

and

B

, where

AB

is the diameter of

K_1

. A point

P

K_2

and inside

K_1

is also given.
Using only a "T-square" (i.e. an instrument which can produce a straight line joining two points and the perpendicular to a line through a point on or off the line), find a construction for two points

C

and

D

K_1

such that

CD

is perpendicular to

AB

and

\angle CPD

is a right angle.

Problem Statement