Let two sides of an isosceles right-angled triangle are of measure "a"Area of triangle =200cm2. (given)⇒200=21​(a2)⇒ a=20cmNow,Hypotenuse =(a2+a2)​=(2a2)​=2​a =202​=20× 1.414=28.28⇒ Hypotenuse is 28.28cmPerimeter of triangle = Sum of all the sides =2a+ Hypotenuse=40+28.28=68.28⇒ Perimeter of triangle is 68.28cm.