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1 vote
You have this information about ΔABC, ΔDEF, and ΔGHI:

AB = DF

AB = GI

BC = HI

DE = HI

m∠B = m∠D = m∠I

Which triangles must be congruent?
ΔABC and ΔDEF only

ΔGHI and ΔABC only

none of the triangles
ΔABC, ΔDEF, and ΔGHI

2 Answers

4 votes

Answer: ΔABC, ΔDEF, and ΔGHI

Explanation:

Given: In ΔABC, ΔDEF, and ΔGHI:

AB = DF AB = GI

BC = HI DE = HI

m∠B = m∠D = m∠I

In ΔABC and ΔGHI

AB = GI [given]

BC = HI [given]

m∠B = m∠I [given]

[ here m∠B and m∠I are the included angle of ΔABC and ΔGHI]

ΔABC ≅ ΔGHI [by SAS congruence postulate]

In ΔABC and ΔDEF

AB = DF [given]

BC = DE [ Since BC = HI and DE = HI so by transitive property BC = DE]

m∠B = m∠D [given]

[ here m∠B and m∠D are the included angle of ΔABC and ΔDEF]

ΔABC ≅ ΔDEF [by SAS congruence postulate]

Now, since ΔABC ≅ ΔGHI and ΔABC ≅ ΔDEF

ΔGHI ≅ ΔDEF [transitive property]

Hence, all the given triangles ΔABC, ΔDEF, and ΔGHI are con gruent to each other.

User Sandeepsure
by
7.3k points
1 vote
ΔABC, ΔDEF, and ΔGHI

I think all triangles are congruent. 2 sides and 1 angle of each triangle is has the same measure. Making these triangles congruent in SAS theorem.
User Nick Graham
by
8.0k points