# trominoes problem

3 views

### Anne B

Nov 27, 2020, 4:37:44 PM11/27/20
to FIGG
I posted this, about a math problem involving trominoes.

https://aelanwave.wordpress.com/2020/11/27/trominoes-problem/

I’ll give the problem here, in case you want to think about it before reading my solutions:

> Show that 21 right trominoes and one monomino will cover an 8 x 8 board regardless of where the monomino is placed.

> Context: A monomino is a single square. A right tromino is three squares stuck together in an L-shape.

Looking for feedback on:

1) Is my post clear? Were you able to understand it? If not, which parts were unclear?

2) Did I say anything false?

2) Anyone know of an app that can produce graphics like the drawings I did? I might or might not look into it.

### Max Kaye

Jan 18, 2021, 6:56:53 AM1/18/21
On Fri, 27 Nov 2020 16:37:35 -0500 Anne B <anne...@gmail.com> wrote:

> I posted this, about a math problem involving trominoes.
>
> https://aelanwave.wordpress.com/2020/11/27/trominoes-problem/
>
> I’ll give the problem here, in case you want to think about it before reading my solutions:
>
> > Show that 21 right trominoes and one monomino will cover an 8 x 8 board regardless of where the monomino is placed.
>
> > Context: A monomino is a single square. A right tromino is three squares stuck together in an L-shape.
>
>
>
> Looking for feedback on:

misc feedback:

I thought it was good, I liked it :)

I like your drawings. I initially (scrolling up/down before reading) worried about overhead and thought that if you had spare capacity then drawing them out nicely was okay/good. but b/c they're more than just notes from you working something out -- they're more integral to the post -- I like that they were neat and carefully done.

It was good that you included the maths-y solution too, it gave me a different sort of 'aha' and it was neat to see the numbers side already done (so I didn't have to think about it, which i wouldn't have done if it wasn't there). I wouldn't have cared if you didn't have superscript formatting for exponents, but it's a nice to have.

> 1) Is my post clear? Were you able to understand it? If not, which parts were unclear?

Yes, I didn't have to read closely to follow (easy to read), and got the big 'aha' moment near the end of the post -- your images were v helpful. I got a little 'aha' moment when reading the wolfram paragraph, and the maths-y induction bit.

> 2) Did I say anything false?

I didn't notice anything.

> 2) Anyone know of an app that can produce graphics like the drawings I did? I might or might not look into it.

I use inkscape occasionally for drawing diagrams and geometric stuff. it's a vector image editing program. it's also free and open source and available on some app stores. not on mobile AFAIK.

I use photoshop (illustrator too) for some diagrams, examples:
https://curi.us/2396-new-community-website-features-and-tech#151
https://curi.us/2395-new-community-website-project#57

I usually use a graphics tablet for those, but they do geometry too.

Vector editing programs (inkscape, illustrator) are nice for this sort of thing because you can group objects and manipulate / duplicate entire groups. you can do that too with photoshop (via layers and layer groups) but scaling stuff will be worse b/c it's using pixels not vectors, and it'd be clunky by comparison.

--
Max
xk.io

I post my FI work/articles/exercise/practice here:
https://xertrov.github.io/fi