My concept of what this site will be is changing. It is not longer "how to answer questions" but "how to learn maths"
I don't want a step by step guide for solving problems. I want to build understanding not "monkey see, monkey do" skills. I don't say that to be rude to those who don't understand maths. I say it because I want students of maths to become mathematicians rather than just people who can (or could at one point) pass a maths test.
Maths builds on a few agreed upon definitions. For example:
a full turn is 360 degrees.
That is agreed upon. For all intents: 360 is a made up number. A nice choice, but we could have chosen other numbers.
Other facts follow naturally. Such as the number of degrees in a half turn.
How to answer questions, such as finding angles on a straight line, follows from an understanding of what it means to turn through an angle. Or to turn through one angle after another.
I did start this website with step-by-step guides to solving Pythagoras and trigonomtry questions. But now I am convinced that this illustrates how little we have actually taught students about formulas. To someone who understands formulas: a first, basic lesson on these topics should not go beyond listing the formulas and providing labelled triangles. This gives all of the instructions. What to do can be worked out from just that. And there is huge power in that efficiency.
On the other hand: there is nothing but tedium and pointless repition in the "do it by rote" method. If the formulas and labelled triangles are not enough for you: start somewhere else; learn as a mathematician by working things out and understanding. Then you can come back to Pythagoras when your understanding of more basic concepts has improved.
You may take longer, but the result will be that you need to memorise less and can answer a far wider range of questions.