Given the side lengths of some triangle:
[tex]\begin{gathered} L_1=84 \\ L_2=96 \\ L_3=60 \end{gathered}[/tex]Let us suppose that there exists another triangle with these side lengths:
[tex]\begin{gathered} L_1^{\prime}=84 \\ L_2^{\prime}=96 \\ L_3^{\prime}=60 \end{gathered}[/tex]Based on these, we can say that:
[tex]\begin{gathered} L_1\cong L_1^{\prime} \\ L_2\cong L^{\prime}_2 \\ L_3\cong L^{\prime}_3 \end{gathered}[/tex]Then, using the Side-side-side theorem, we conclude that both triangles are congruent, so this triangle is unique