### Polydron

This activity investigates how you might make squares and pentominoes from Polydron.

### Eight Dominoes

Using the 8 dominoes make a square where each of the columns and rows adds up to 8

### Prime Magic

Place the numbers 1, 2, 3,..., 9 one on each square of a 3 by 3 grid so that all the rows and columns add up to a prime number. How many different solutions can you find?

# Coordinate Challenge

##### Stage: 2 Challenge Level:

Here is a grid:

Can you position these ten letters in their correct places according to the eight clues below?

Clues:

The letters at $(1, 1),$ $(1, 2)$ and $(1, 3)$ are all symmetrical about a vertical line.

The letter at $(4, 2)$ is not symmetrical in any way.

The letters at $(1, 1),$ $(2, 1)$ and $(3, 1)$ are symmetrical about a horizontal line.

The letters at $(0, 2),$ $(2, 0)$ have rotational symmetry.

The letter at $(3, 1)$ consists of just straight lines.

The letters at $(3, 3)$ and $(2, 0)$ consist of just curved lines.

The letters at $(3, 3),$ $(3, 2)$ and $(3, 1)$ are consecutive in the alphabet.

The letters at $(0, 2)$ and $(1, 2)$ are at the two ends of the alphabet.

You could use this interactivity to try out your ideas.

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