question_answer

In the given figure, AB is a diameter of a circle and CD is perpendicular to AB, if AB=10 cm and \[AE=2\]cm, then what is the length of ED is

A)  5 cm                           

B)  4cm      

C)  10 cm                         

D)  20 cm

Correct Answer: B

Solution :

(b):- In \[\Delta OED\]. \[{{\left( OD \right)}^{2}}={{\left( DE \right)}^{2}}+{{\left( EO \right)}^{2}}\] \[\Rightarrow \]\[{{\left( 5 \right)}^{2}}={{\left( DE \right)}^{2}}+{{\left( 3 \right)}^{2}}\Rightarrow {{\left( DE \right)}^{2}}=25-9=16\] \[\therefore \]\[DE=4\] cm