In the given right angled isosceles triangle ABC, if AC = 10 cm then the area of triangle (in cm2) is ___.
25
In right angled isosceles triangle ABC, B = 90∘
AB=BC
So,θ = α
cos θ = 1√2 at θ =45∘
So, ABAC=1√2
AB=AC√2
AB=5√2 cm
And sinθ =1√2 at α =45∘
So, BCAC=1√2
BC=5√2cm
Area of triangle=12 (Base × Height)
=12(5√2 × 5√2)
=25 cm2