How do i checkmate someone in chess?

By trying to trap the king where he move himself anymore, where their are no more moves for him to be safe again.

Step-by-step explanation:

You need to be careful to distinguish area from volume. You could delete a 4x4x5 cuboid if you were figuring volume, but it's different for area.

If you look at this figure from any direction in which the 5-inch length is left-to-right across your field of vision, you see only a face that is 8 inches by 5 inches. Those 4 faces add to 4 * (8 in)*(5 in) = 160 in^2.

If you look at the figure from the side, so you see an L shape, You can consider that to be an 8-inch square with a 4-inch square cut out of it. That area is 64 in^2 -16 in^2 = 48 in^2. (Alternatively, it is a 4x8 rectangle plus a 4x4 square. It still adds up to 48 in^2.) The sum of the areas of these left and right sides is then 2*48 in^2 = 96 in^2.

The total area is then 160 in^2 +96 in^2 = 256 in^2, the 4th selection.