LEARN MATH STEP BY STEP THROUGH VERY EASY PROCESS

SECANT & TANGENT

__Secant
and Tangent –__

**When a straight line that
intersects a circle at two distinct points will be considered as a secant of
the circle. In the figure, PQ will be considered as a secant of the
circle with center at ‘O’.**

**A straight line that
intersects a circle at only one point is called a tangent to the circle at that point. In the figure,
the line BA is a tangent to the circle at A. The length of the line segment BA
is known as the length of the tangent from B and point A is known as the point of contact of the
tangent.**

__Property-1)__ The Tangent at any point of a circle and the radius through the
point should be perpendicular to each other.

**In the figure, ∠OAB = 90⁰**

__Property-2)__ There is one, and only one, tangent must be at any point of a circle.

**In the figure, since BA and CA
are tangents to the circle at A, CAB is a straight line**

__Property-3)__ Two tangents can be drawn to a circle from a point that will be
situated outside the circle.

**In the figure, AD & AE are
two tangents to the circle from point A outside the circle.**

__Property-4)__ If two tangents are drawn to a circle from a point outside the
circle then the tangents will be equal in length.

**
In
the figure, AD & AE are two tangents to the circle drawn from A outside the
circle, so AD = AE**