SOLUTION: What is the formal proof of the theorem "The diagonals of an isosceles trapezoid are congruent"?

Question 1143438: What is the formal proof of the theorem "The diagonals of an isosceles trapezoid are congruent"?
Answer by ikleyn(52803)   (Show Source): You can put this solution on YOUR website!
.
See the lesson
    -Diagonals of an isosceles trapezoid are congruent,
in this site and find the proof there.

Also, you have this free of charge online textbook on Geometry
    GEOMETRY - YOUR ONLINE TEXTBOOK
in this site.

The referred lesson is the part of this online textbook under the topic "Properties of trapezoids".

Save the link to this online textbook together with its description

Free of charge online textbook in GEOMETRY
https://www.algebra.com/algebra/homework/Triangles/GEOMETRY-your-online-textbook.lesson

to your archive and use it when it is needed.

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