Sum of Geometric Series Problem Sn=a+ar+ar^2+...+ar^n-1, S2=3.5, S3=11.375, and r<0. Find a and r.
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The answer to this question is c

If two sides of a triangle are congruent, then the angles opposite those sides are congruent. the converse of the base angles theorem, states that if two angles of a triangle are congruent, then sides opposite those angles are congruent.