Chapter 4 - Congruent Triangles - 4-2 Triangle Congruence by SSS and SAS - Practice and Problem-Solving Exercises - Page 232: 26

$SSS$ postulate

For this problem, $\overline{JE}$ is congruent to $\overline{SF}$, $\overline{JF}$ is congruent to $\overline{SV}$, and $\overline{EF}$ is congruent to $\overline{FV}$. We have three sides on one triangle congruent to three sides on the other triangle. Therefore, we can use the $SSS$ postulate to prove that these triangles are congruent.