Given: A B C D is a rectangle. Prove: The diagonals of A B C D are congruent. The coordinates of rectangle ABCD are A(0, 0) , B(a, 0) , C(_,_), and D(0, b) .The length of AC¯¯¯¯¯ is equal to ____.The length of BD¯¯¯¯¯ is equal to ____.The diagonals of the rectangle have the same length.Therefore, AC¯¯¯¯¯ is congruent to BD¯¯¯¯¯.