Advertisements
Advertisements
प्रश्न
If AD is a median of a triangle ABC, then prove that triangles ADB and ADC are equal in
area. If G is the mid-point of median AD, prove that ar (Δ BGC) = 2 ar (Δ AGC).
Advertisements
उत्तर

Draw AM ⊥ BC
Since, AD is the median of ΔABC
∴ BD = DC
⇒ BD = AM = DC × AM
⇒ ` 1/2 (BD xx AM ) = 1/2 ( DC xx AM)`
⇒ ar (Δ ABC) = ar (Δ ACD) ........ (1)
In ΔBGC , GDis the median
∴ ar (BGD) = area (OGD) ......... (2)
In ΔACD , CG is the median
∴ area (AGC) = area (Δ CGD) ......... (3)
From (1) and (2) , we have
Area (ΔBGD) = ar (Δ AGC)
But, ar (ΔBGC) = 2ar (BGD)
∴ ar (BGC ) = 2ar (Δ AGC)
APPEARS IN
संबंधित प्रश्न
In Q. No 1, if AD = 6 cm, CF = 10 cm, and AE = 8cm, find AB.
ABCD is a parallelogram. E is a point on BA such that BE = 2 EA and F is a point on DC
such that DF = 2 FC. Prove that AE CF is a parallelogram whose area is one third of the
area of parallelogram ABCD.
The figure obtained by joining the mid-points of the adjacent sides of a rectangle of sides 8 cm and 6 cm is ______.
The medians of a triangle ABC intersect each other at point G. If one of its medians is AD,
prove that:
(i) Area ( ΔABD ) = 3 x Area ( ΔBGD )
(ii) Area ( ΔACD ) = 3 x Area ( ΔCGD )
(iii) Area ( ΔBGC ) = `1/3` x Area ( ΔABC ).
The diagonal of a rectangular board is 1 m and its length is 96 cm. Find the area of the board.
The length and breadth of a rectangular piece of land are in the ratio 5 : 3. If the total cost of fencing it at the rate of ₹24 per meter is ₹9600, find its :
(i) length and breadth
(ii) area
(iii) cost of levelling at the rate of ₹60 per m2.
Find the area of a rectangle whose length = 3.6 m breadth = 90 cm
Find the area and perimeter of the following parallelograms
The table given below contains some measures of the rectangle. Find the unknown values.
| Length | Breadth | Perimeter | Area |
| 13 cm | ? | 54 cm | ? |
Find the area of the following figure by counting squares:

