Given the base of an isosceles right angle triangle is $30$ cm.It is required to find the area of the same.
Its quite clear that if the triangle is isosceles right angled triangle, and its base is 30, then the length of perpendicular would also be equal to 30.
By applying the formula for the area of a triangle i.e. $\frac 12$$.b.h$, the area clearly comes out to be $\frac 12$.$30.30=450$.But the answer according to the book is wrong and is 225.Can anyone please explain me how am I wrong?