from math import sqrt
from triangle_semi_perimeter_0 import triangle_semi_perimeter
def triangle_area_heron (slide1,slide2,slide3):
    return sqrt(triangle_semi_perimeter(slide1,slide2,slide3)*(triangle_semi_perimeter(slide1,slide2,slide3)-slide1)*
                (triangle_semi_perimeter(slide1,slide2,slide3)-slide2)*(triangle_semi_perimeter(slide1,slide2,slide3)-slide3))