Given, ∣∣2a2b2cx1x2x3y1y2y3∣∣=2abc ⇒2∣∣abCx1x2x3y1y2y3∣∣=2abc ⇒∣∣abCx1x2x3y1y2Y3∣∣=4abc...(i)
Given, vertices of a triangle are (ax1,ay1),(bx2,by2) and (cx3,cY3) ∴ Area of triangle =21∣∣ax1bx2cx3ay1by2cy3111∣∣=21⋅a1⋅b1⋅c1∣∣x1x2x3y1y2y3abC∣∣ =2abc1∣∣abcx1x2x3y1y2y3∣∣=2abc1(4abc) [from Eq. (i)] =81