Name sides, angles and other unknowns that lack a name. You could name it . This helps you to properly express what you need to do to solve the problem. You can use this name to set up an equation. If you don’t give things name, your notes will get messy, and the solution may disappear into the mess of unorganized information.
Giving things a name is no different than baptizing a newborn baby. In the same way you think it’s natural that a newborn baby should get a name, it’s only natural that things in mathematics should get a name. If calling things seems weird, then name them something you like and see if that helps.
Do you know what Elon Musk named his sixth child? His name is: X Æ A-Xii. As you can see, no need to be afraid of giving things names.