Question

In the adjoining figure, ABCD is a parallelogram and M is the mid-point of AВ. If ar (|| gm ABCD) = 40 cm², then ar (ΔADM) is equal to:

पर्याय

• 5 cm²

• 20 cm²

• 15 cm²

• 10 cm²

Answer 1

10 cm² 

Explanation:

Let AB be the base and h the height of the parallelogram.

Since M is the midpoint, `AM = 1/2 AB`. 

Triangle ADM has base AM and the same height h.

So, `"Area" (ΔADM) = 1/2 xx AM xx h` 

= `1/2 xx 1/2 AB xx h`

= `1/4 xx AB xx h`

= `1/4 xx "Area" ("Parallelogram")` 

= `40/4`

= 10 cm²