Three circles touch each other externally. The distance between their centres is 5 cm, 6 cm and 7 cm. Find the radii of the circles.
The correct option is
B
2 cm, 3 cm, 4 cm
In the figure, let AB=5 cm, BC=6 cm and AC=7 cm
AB=x+y=5 …..(i)
Also
BC=y+z=6
⇒y=6−z
Substituting in (i), we get,
x+6−z=5
⇒x−z=−1 …..(ii)
Also, AC=x+z=7 …..(iii)
Adding (ii) and (iii), we get,
2x=6⇒x=3,∴ y=2, z=4
Therefore, the radii of the circle is 2, 3 and 4 cm