Question

A circle centre o py is a tangent ab is a chord and or is a radius then prove rab=bry

Answer 1

Tangent to a Circle Theorem: A line is tangent to a circle if and only if the line is perpendicular to the radius drawn to the point of tangency. To prove this theorem, the easiest way to do so is indirectly (proof by contradiction)


The angle between the tangent and radius is 90° A tangent to a circle is a line which just touches the circle. Remember: A tangent is always at right angles to the radius where it touches the circle.