UPSC NDA Math Model Paper 5

Given: A (4,4), B(3,- 16) and C(3,-2) are the vertices of the triangle ABC
Let x1=4,y1=4,x2=3,y2=−16,x3=3 and y3=−2
As we know that, if A(x1,y1),B(x2,y2) and C(x3,y3) are the vertices of a Δ ABC then area of Δ‌ABC=

1

2

.|

x1	y1	1
x2	y2	1
x3	y3	1

|
⇒ ⇒A=

1

2

.|

4	4	1
3	−16	1
3	−2	1

|
⇒A=7‌squnits
Hence, option B is the correct answer.