Question

Height of the isosceles triangle is 6 cm.Its perimeter is 36 cm.Find its area

Answer 1

Since perimeter = 36 and base is 16. Each side is 10 (10+10+16 = 36 perimeter) 

In an isoceles triangle, the perpendicular from the 3rd point of the triangle on the base divides the base. 

So half of base and height and one side becomes a right triangle 
Now using pythagoras theorem 
h^2 = side^2 - (base/2)^2 
= 100 - 64 = 36 
h = 6 

Area of traiangle = 1/2 * b * h 
= 1/2 * 16 * 6 
= 48 sq cm. 

Hope this helps