To determine the congruence between the triangles, we compare their side lengths.
Given information:
For △ABC:
- AB=5 cm
- AC=8 cm
- BC=4 cm
For △DBC:
- BD=8 cm
- CD=5 cm
- BC=4 cm (This side is common to both triangles)
Step 1: Compare the corresponding sides.
Let's list the sides of △ABC and try to match them with the sides of △DCB.
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Side AB=5 cm in △ABC.
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Side DC=5 cm in △DCB.
So, AB=DC.
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Side BC=4 cm in △ABC.
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Side CB=4 cm in △DCB.
So, BC=CB.
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Side AC=8 cm in △ABC.
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Side DB=8 cm in △DCB.
So, AC=DB.
Step 2: Determine the congruence criterion.
Since all three corresponding sides of △ABC are equal to the three corresponding sides of △DCB, the triangles are congruent by the SSS (Side-Side-Side) congruence criterion.
Step 3: Write the correct congruence statement.
To write the congruence statement, we need to match the vertices correctly based on the equal sides:
- Since AB=DC, vertex A corresponds to vertex D, and vertex B corresponds to vertex C.
- Since BC=CB, vertex B corresponds to vertex C, and vertex C corresponds to vertex B.
- Since AC=DB, vertex A corresponds to vertex D, and vertex C corresponds to vertex B.
Combining these, we get the correspondence:
- A ↔ D
- B ↔ C
- C ↔ B
Therefore, the correct congruence statement is △ABC≅△DCB.
Step 4: Check the given options.
(1) △ABC≅△DBC, by SAS - Incorrect vertex correspondence and criterion.
(2) △ABC≅△DCB, by SAS - Incorrect criterion.
(3) △ABC≅△DBC, by SSS - Incorrect vertex correspondence.
(4) △ABC≅△DCB, by SSS - Correct vertex correspondence and criterion.
The final answer is 4.