Question 547047
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I'll give you the strategy and you can set up your own two-column proof.


Angle SRT is given congruent to Angle STR, so go find the converse of the theorem that says the two base angles of an isosceles triangle are equal to be able to say that the two sides opposite the two given congruent angles are congruent.  Do the same thing for the lower triangle.  Then using Angle-Side-Angle (the side being the segment RT which is congruent to itself by Reflexive Congruence) show that the upper and lower triangles are congruent.  Then by CPCTC, all four sides of the quadrilateral are congruent.  Therefore, a rhombus.  QED.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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