Question 921156
fghi is a rectangle.
opposite sides of a rectangle are parallel and congruent.
all angles are 90 degrees.
you want to prove that the diagonals are congruent.
the following documents shows one way to do this.
instead of just saying properties of a rectangle, you could say.
opposite sides of a rectangle are congruent.
all angles of a rectangle are equal to 90 degrees.
these are both properties of a rectangle and should be considered as given.
you draw the two diagonals and then you prove that the triangles formed are congruent by SAS and then you prove the diagonals are congruent because they are corresponding side of congruent triangles.
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