Out of all the regular polygons there are only three you can use to tile a wall with: the square, the equilateral triangle, and the regular hexagon. All the others just won't fit together.

Trying to fit pentagons around a point.
It’s quite easy to prove this. A regular polygon with sides has interior angles of
Suppose you try and make a tiling by fitting several copies, say of them, around a point so that they all meet at a corner (see the image above). Then the
angles must add up to 360 degrees. If they add up to less there will be a gap, and if they add up to more then copies of the polygon will overlap.
So we need
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which means that
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The term on the right hand side can be rewritten to give
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Since is a whole number (the number of copies of the polygon you are fitting together), this means that
must also be a whole number. Therefore
can only be equal to 4, 2, and 1, which means that
can only be equal to 6, 4, and 3.

Trying to fit a third polygon with two copies offset against each other.
You could also try to make a tiling in which a corner of the polygon does not necessarily meet the corner of a neighbouring copy, but sits at some point along the neighbouring copy’s side. That neighbouring copy would therefore have an interior angle of 180 degrees at
(since
is in the interior of one of its sides). To make a tiling you would have to fill the remaining 180 degrees with
copies of the polygon, so you would need
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Using a similar argument as above you can convince yourself that this only works when or
You can read more about tilings on Plus.
Comments
Tiling a wall and polygons
You may not be able to tile a wall with pentagons, but you can make a really cool solid by lining the sides of pentagons... :-)
translation
The article translated into Arabic: https://goo.gl/AlRmbR
Non Regular Pentagons
Of course it is possible to tile with non regular pentagons. There are 15 different types with the latest being discovered in 2015