This number will be used to tell you how far your seismograph is from the epicenter of the earthquake. Measure the distance between the first P wave and the first S wave. In this case, the first P and S waves are 24 seconds apart.
Given that two angles and an included side of triangle ΔGBD are equal to the corresponding two angles and an included side of triangle ΔKCA, therefore, ΔGBD ≅ ΔKCA by the Ange-Side-Angle rule of congruency, therefore, we have;
Segment is congruent to segment by Congruent Parts of Congruent Triangles are Congruent, CPCTC.