Question

find the area of an isosceles right triangle if one of the right sides is 20cm long

Answer 1

given 
1side =20 cm 
angle sum property - addition of 2 sides greater than 3rd
isoceles - 2 sides equal 
both the sides so the sides should be equal and greater than 20
so the sides = 11 cm
area of triangle = bXh/2
 h = 20 b=11 
so area = 20 X 11 /2
 area = 10 X 11      area =  110 cm square