A) 450
B) 308
C) 154
D) 77
Correct Answer: C
Solution :
\[BD=DC=7\sqrt{3}\,cm\] \[AD=\sqrt{A{{B}^{2}}-B{{D}^{2}}}\] \[=\sqrt{{{(14\sqrt{3})}^{2}}-{{(7\sqrt{3})}^{2}}}\] \[=\sqrt{(14\sqrt{3}+7\sqrt{3})(14\sqrt{3}-7\sqrt{3})}\] \[=\sqrt{21\sqrt{3}\times 7\sqrt{3}}=21\,cm\] \[\therefore \] OD = Radius of circle \[=\frac{1}{3}\times 21=7\,cm\] \[\therefore \] Area of circle \[=\pi {{r}^{2}}\] \[=\frac{22}{7}\times 7\times 7=154\,sq\,cm\]You need to login to perform this action.
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