Create a python function to compute the area of a triangle with given sides.
a = 3
b = 5
c = 4
def calculateTriangleArea(a, b, c): 
    s = (a + b + c) / 2
    area = (s*(s-a)*(s-b)*(s-c)) ** 0.5
    return area
  
area = calculateTriangleArea(a, b, c) 
print("Area of triangle is %.2f" % area)