Answer:
![\boxed {\boxed {\sf Solid \ to \ liquid}}](https://img.qammunity.org/2021/formulas/chemistry/high-school/i3d4tbebk3vmm2at9zotxipmdetrvvrdug.png)
Step-by-step explanation:
When heat is added to matter, the temperature rises. The average kinetic energy also increase and the matter melts.
When matter melts, it turns from a solid to a liquid. So, the melting point of matter is the temperature where it changes from the solid state of matter to the liquid state of matter.