Given: Rectangle ABCD Prove: diagonal AC is congruent to diagonal BD?

1 Answer
Nov 21, 2015

See the proof below

Explanation:

Since ABCDABCD is rectangle, the following relationships of congruence are true:

AB~=CDABCD
AD~=BCADBC
/_ABC~=/_BCD~=/_CDA~=/_DAB=90^oABCBCDCDADAB=90o

Therefore, Delta ABC ~= Delta ABD as right triangles with congruent catheti BC and AD and shared cathetus AB.

From congruence of these triangles follow the congruence of their hypotenuses AC and BD.