# Tridots

## Find all the triangles that can be drawn by joining dots.

There is a printable worksheet to go with this activity.

## Investigate other polygons that can be drawn on a 3 by 3 grid.

#### Polygon Areas

Investigate which polygons have an area of 4 square units on this interactive dotty grid.

The short web address is:

Transum.org/go/?to=areas

##### Suggested

Calculate the areas of all the possible quadrilaterals that can be constructed by joining together dots on this grid.

The short web address is:

#### Area Two

How many different shapes with an area of 2 square units can you make by joining dots on this grid with straight lines?

The short web address is:

Transum.org/go/?to=area2

All the possible triangles and the solutions to other Transum puzzles, exercises and activities are available here when you are signed in to your Transum subscription account. If you do not yet have an account and you are a teacher, tutor or parent you can apply for one by completing the form on the Sign Up page.

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Investigations Home

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A mathematical investigation is quite different to other mathematical activities. The best investigations are open ended and allow students to choose the way they work and how they record their findings. It is one of the few occasions when 'going off on a tangent' is not only acceptable but actively encouraged (within reason).

Students may ask for 'the answers' but this supposes that the activity is closed. Investigations can always be extended by varying the initial instructions or asking the question 'what if...?'. Sometimes students point out that the instructions are ambiguous and can be interpreted in different ways. This is fine and the students are encouraged to explain how they interpreted the instructions in their report.

Some students may benefit from a writing frame when producing the reports of their investigations. Teachers may suggest sections or headings such as Introduction, Interpretation, Research, Working and Conclusion or something similar.

## Here are some other activities you may be interested in:

#### Jugs

The classic problem of using two unmarked jugs to measure exactly a given quantity. The Transum version is interactive and awards a virtual trophy for each of the levels completed.

#### Ratio

A self marking exercise on using ratio notation, reducing a ratio to its simplest form and dividing a given quantity into a number of parts in proportion to a given ratio. So far this activity has been accessed 59651 times and 22985 Transum Trophies have been awarded for completing it.

For Students:

For All: