Wasn't sure how to execute a checkmate from this position. (New player)

Here is a game I had today. My opponent resigned, I had a tremendous advantage but also wasn't sure how to checkmate him (I was black). Take a look!

Thank you very much Sqod! you made it look easy

You're welcome. My written response was aborted and lost from a page failure so I didn't bother to retype my explanation.

It's an interesting position in that it's so awkward for Black, and you threw me off by asking how to *mate* from there. I don't believe Black can mate yet, but he can stifle counterplay by first trading off pieces. It doesn't even matter if White forks Black and wins Black's rook at the end of the first line because that stifles counterplay, too, and leads to K + R + 3P vs K ending, which is easy for Black to win.

Incidentally, White's knight is hanging, too.

General principle: simplify when you're ahead in material. The more pieces you trade, the simpler the win gets.

If you find a way to trade rooks, I think you'd agree that the RPPP vs N ending is a very simple win. If not, then find a way to trade your rook for the knight, and I imagine you'd agree KPPP vs K is trivially easy even for a beginner. 

It's actually simple. The key here is to make sure that the King is in check, and cannot block the attack by:

a) putting another piece in the way or,

b) taking the piece that is executing the check or,

c) moving to an adjacent square.

Volia, and you have a checkmate.

P.S. You are welcome!

But it ain't easy to see from 800 metres away.

@Chess_Noob800m

Are you familiar with the technique to checkmate a bare king using one king and one rook? If so, then this endgame should not be too difficult also. The idea here (as everyone else here pointed out earlier) is to try and catch either of White's pieces first (the rook and the knight are active runners in the game so catch them before they circle around in celebration) to reduce any possible attack from your opponent. If you manage to catch both of his pieces, it would be even better because the opponent's bare king walks slowly (but watch out for stalemates). Then using your knowledge of the king and rook versus bare king endgame, or your knowledge of promoting pawns to queens safely, you should be able to bring home the full point.

Thank you for returning and rewriting it! I appreciate that!

Thanks for that tip! I some what knew about it but needed that reinforcement! I will keep it in my mind whenever at an end game and up on materials

That's exactly what happened. I knew I was winning but wasn't sure where to move the rooks... now I know

Thank you!!

hahaha sometimes it's easier to just run an 800m race!

I'm not familiar with the technique to checkmate a bare king using one king and one rook yet, but I will look at it!

Just for completeness' sake. 

harharhar

@Morphried

That was funny. I did not even consider that the pawns could be promoting (now that you mentioned it, I did not see the board axes in the first diagram), but in that case I would be wondering how the White king travelled to h8 in the first place. In such situations I will simply assume that the pawns are not promoting.

@eric0022

Actually he turned the chessboard 180° before he put the pieces.

I have verified from the toggle engine analysis button in the first diagram that the Black pawns are on a7, b5 and d7. Had the pawns been promoting, Morphried would have probably been able to win the game much more easily than in the actual game where the pawns are not promoting.