MENU
Question -

In the given figure, triangle ABC is right-angled at B. Given that AB = 9 cm, AC = 15 cm and D, E are the mid-points of the sides AB and AC respectively, calculate
(i) The length of BC
(ii) The area of ΔADE



Answer -

We have  right angled at B.
 
It is given that  and 
D and E are the mid-points of sides AB and AC respectively.
(i) We need to calculate length of BC.
In  right angled at B:
By Pythagoras theorem,
 
Hence the length of BC is 
(ii) We need to calculate area of  .
In  right angled at B, D and E are the mid-points of AB and AC respectively.
Theorem states, the line segment joining the mid-points of any two sides of a triangle is parallel to the third side and equal to half of it.
Therefore,  .
Thus,   (Corresponding angles of parallel lines are equal)
And
 .
area of   
D is the mid-point of side AB .
Therefore, area of   
 
Hence the area of is  .


Comment(S)

Show all Coment

Leave a Comment

Free - Previous Years Question Papers
Any questions? Ask us!
×