Find the area of a triangle whose vertices are A (3, 2), B (11, 8) and C(8, 12). [3 MARKS]
Concept : 1 Mark
Application : 1 Mark
Calculation : 1 Mark
Let A=(x1,y1)=(3,2),
B(x2,y2)=(11,8)
and C=(x3,y3)=(8,12) be the given points. Then,
Area of ΔABC=12|x1(y2−y3)+x2(y3−y1)+x3(y1−y2)|
Area of ΔABC=12|3(8−12)+11(12−2)+8(2−8)|
Area of ΔABC=12|−12+110−48|=25 sq. units