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Answers are in the format;
Statement Reasons
Problem 1
1) AB = CB given
2) AD = CD definition of midpoint
3) DB = DB reflexive property
4) ABC = CBD side-side-side congruency
Problem 2
1)AB = CB given
2) m<A = m<C given
3) CD = CD reflexive property
4) ABD = CBD side-angle-side congruency
5) AD = CD corresponding parts of congruent triangles are . congruent
Problem 3
1) CG = CD Given
2) CGD-isosceles triangle Definition os isosceles triangle
3) m<CDG = m<CGD Base angles theorem
4) DF = GF Given
5) CDE = CFG side-angle-side
6) CE = CF corresponding parts of congruent traingles . are congruent