10th Class Mathematics Triangles Question Bank MCQs - Triangles

  • question_answer
    In figure, if  \[\frac{AD}{DC}=\frac{BE}{EC}\] and \[\angle CDE=\angle CED,\] then:                
     

    A) \[\text{BC}=\text{AC}\]

    B) \[\text{AB}=\text{AC}\]

    C) \[\text{AB}=B\text{C}\]

    D) \[CE=DE\]

    Correct Answer: A

    Solution :

    [a] In \[\Delta ABC,\]
    we have    \[\frac{AD}{DC}=\frac{BE}{EC}\]              (Given)
    Therefore, by the converse of basic proportionality theorem.
    we have. \[DE||AB\]
    \[\Rightarrow \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\angle CDE=\angle CAB\]
    and  \[\angle CED=\angle CBA\] (Corresponding angles)
    But,        \[\angle CDE=\angle CED\]               (Given)
    \[\therefore \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\angle CAB=\angle CBA\]
    \[\Rightarrow \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\angle A=\angle B\,\,\,\,\,\,\,\,\Rightarrow \,\,\,\,\,\,BC=AC\]
    (Sides opposite to equal angles are equal)
     


You need to login to perform this action.
You will be redirected in 3 sec spinner