Question

find the area of a isosceles triangle whose base is 2 cm and two equal sides are 4 cm.

by herons formula​

Answer 1

Area of a triangle = Square root of s(s-a)(s-b)(s-c), where a, b and c are the sides of the triangle and s is the semi-perimeter.
s = (2+4+4)/2 = 5
Area = Square root of 5(5-2)(5-4)(5-4)
= Square root of 5*3*1*1
= Square root of 15 cm^2