Question

If the length of the common chord of two intersecting equal circles be 6 cm and if the radius of each circle be 5 cm then the distance between the centers of the circle is

• A. 7 cm
• B. 8 cm
• C. 9 cm
• D. none

Answer 1

Answer: (B)

8 cm

The figure is shown in image

Now apply Pythagoras theorem in $\Delta OAB$

$O{A}^2=A{B}^2+O{B}^2$

$5^2=O{B}^2+3^2$

$OB=4$c.m.

similarly for $\Delta ABD$

$BD=4$c.m.

Hence Distance b\w center of the circles is $8$ c.m.