Question

pls solve this question​

Answer 1

Answer:

Step-by-step explanation:

let the third vertices of triangle =(x,y)

Centroid = (x1 + x2 + x3)/3 , (y1 +y2 + y3)/3

(4,-8). =. (-9 +1 +x)/3 ,. ( 7 + 4 + y)/3

(4,-8) =. (-8 +x) /3 , (11 + y) /3

4 = (-8+ x ) /3. , -8 = (11 +y ) /3

12 +8 =x. ,. -24-11 = y

x= 20 , y = -35

Area of the triangle ( -9,7) , (1,4) ,(20,-35)

= 1/2 [ x1 (y2 -y3) + x2 (y3 -y1) + x3 ( y1 -y2)]

= 1/2 [ -9 (4 +35) +1 (-35-7) +20 (7 - 4) ]

= 1/2 [-9 ×39 - 1× 42 +20 × 3 ]

= 1/2 [ -351 -42 +60 ]

= 1/2 [-393 +60] = 1/2 (-333) = -166.5

Neglected negative sign so area is 166.5