Question

in a quadrilateral ABCD, /_B=90degree. if AD^2=AB^2+BC^2+CD^2,prove that /_ACD=90degree

Answer 1

see the detail my friend it is explained in the photo

Answer 2

I draw an imaginary picture of this quadrilateral, then from triangle ABC, I got pythagorus theorem, then from the given clue I used it, then I got AD^2=AC^2 +CD^2 which indicates that triangle ACD is a right angle where angle C is 90°