- If
is a tangent to the circle at , then is perpendicular to .Condition:
is a tangent atResult:
Reference: tangent
radius - If
is perpendicular to , then is a tangent to the circle at .Condition:
Result:
is a tangentReference: converse of tangent
radius - If
is a tangent to the circle at , any straight line perpendicular to and passing through must pass through the centre.Condition:
is a tangent at and a perpendicular line passing throughResult: The straight line must pass through the centre
Reference: line passing through the pt of contact
tangent passes through centre - Given that
and are two tangents to the same circle. Then .Condition: Two tangents
andResult:
Reference: tangent properties
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- If
is a tangent to the circle, then the angles in alternate segment equal.Condition:
is a tangentResult:
Reference:
in alt. segment - If the angles in the alternate segment equal, then
is a tangent to the circle at .Condition:
Result:
is a tangent to the circleReference: converse of
in alt. segment