Olympiad workbookIOQMProperties of Triangles
In a quadrilateral A B C D , it is given that A B=A D=13, B C=C D=20, B D=24 . If r is the radius of the circle inscribable in the quadrilateral, then what is the integer closest to r ?
Correct answer
8
Step-by-step solution
aligned Area of A B C D & = Area of A B D+ Area of B C D & = 25 12 12 1 + 32 8 12 12 & =60+192=252 Inradius(r) & = Area semi-perimeter = 252 33 = 84 11 =7 . 64 aligned Hence integer nearest to r is 8.