To Be Solved
To Come Undone, To Be Cleared
intransitive verb, ichidan verb
とける
解ける (とける) To Be Solved, To Come Undone, To Be Cleared
溶ける (とける) To Melt, To Dissolve, To Thaw
解く (とく) To Solve, To Solve Something, To Untie Something
解ける is intransitive because you don't have a care ける in the world.