The Total solution for NCERT class 6-12
The lengths of two parallel chords of a circle are 6 cm and 8 cm. Ifthe smaller chord is at a distance 4 cm from the centre, what is the distanceof the other chord from the centre?
Consider the followingdiagram
Here AB and CD are 2parallel chords. Now, join OB and OD.
Distance of smallerchord AB from the centre of the circle = 4 cm
So, OM = 4 cm
MB = AB/2 = 3 cm
Consider ╬ФOMB
OB2┬а=OM2+MB2
Or, OB = 5cm
Now, consider ╬ФOND,
OB = OD = 5 (sincethey are the radii)
ND = CD/2 = 4 cm
Now, OD2=ON2+ND2
Or, ON = 3 cm.