In the diagram, two circles are tangent to each other at

Last updated: 8/7/2022

In the diagram, two circles are tangent to each other at point B. A straight line is drawn through B cutting the two circles at A and C, as shown. Tangent lines are drawn to the circles at A and C. Prove that these two tangent lines are parallel. In the diagram, AB and BC are chords of the circle with AB < BC. If D is the point on the circle such that AD is perpendicular to BC and E is the point on the circle such that DE is parallel to BC, prove that LEAC+ ZABC = 90°.