Area of a triangle = 12×(b×h)
where h is the length of perpendicular drawn to side of length b.
If triangle is right angle triangle then area = 12× (product of the length of perpendicular sides)
Else we can use Herons formula
A=√s(s−a)×(s−b)×(s−c)
Where a,b,c are length of side of triangle.
s=a+b+c2