Page 1 - Lesson note 4 Equal Chords-equidistant- circle Ch.- 10 Circle

SAI International School

Class -IX

Mathematics
Chapter-10: Circle

Lesson Notes-4

Sub topic : Equal chords and their distances from center

Distance of a line from a point
Let AB be a line and P be a point. Since there are infinite numbers of points on a line, if
we join these points to P, you will get infinitely many line segments PL1, PL2, PM, PL3,
PL4, etc

Which of these is the distance of AB from P?
Out of these line segments, the perpendicular from P to AB, namely PM will
be the least. The least length PM to be the distance of AB from P.
So we may say that:
The length of the perpendicular from a point to a line is the distance
of the line from the point.
If the point lies on the line, the distance of the line from the point is zero.
A circle can have infinitely many chords. We may observe by drawing
chords of a circle that longer chord is nearer to the centre than the smaller
chord