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Basic shapes

# Recognizing shapes

Recognizing shapes.

## Want to join the conversation?

• can any one help me with remembering what tri and uni and octi quad and hex and other things like that?
• You can remember the prefix `tri-` with the word `tricycle`, as it is a bicycle, but with `3` wheels. A `triangle` has `3` sides and angles. See more below:
`Octi-` as in `octopus`. An `octopus` has `8` arms, and an `octagon` has `8` sides and angles.
`Quad-` as in `quad-bike`. A `quad-bike` has `4` wheels, and a `quadrilateral` has `4` sides and angles.
`Hex` I'd just memorize. :)
Need any more help? Just say so! :)
• What does "hex" mean?
• "Hex" or "hexa" is a prefix that means 6 of something.
• Can someone help with remembering the names for 123456789?
• do you mean the prefixes? Here:

1 uni/mono - think about unicorns or monloges
2 bi - think about bicycles
3 tri - tricycles
4 tetra - if you play tetris, you'll know it!
5 penta - sorry, I don't really have one for this...
6 hexa - just remember that if it starts with a 'h', it's either 6 or 7. And since 'hexa' contains the letter 'x', you know it is six. Seven is simply the other one :)
7 hepta - refer to above
8 octo - octopus
9 nona - sounds like nine, doesn't it?

Hope this helps!!
• What Sal mean " these will cross the other opposite side " when he explain trapezoids ?
• He means that those two line segments are not parallel. If you were to lengthen them, eventually they would intercept each other, or cross, as Sal says.
• what do you call a shape with a hundred sides?
• A hundred-sided polygon is called a hectogon.

The word hectogon is a combination of the following Greek roots:
- hecto = 100
- gon = side

A thousand-sided polygon is called a chiliagon. This word is derived from the Greek word "chilioi", meaning 1000. (Our prefix kilo also comes from the root "chilioi".)

Hope this helps!
• what is the name of shape that has 30 sides
• Triacontagon!
(1 vote)
• How do they come up with the names of the shapes?
• Many of the shape names depend on how many sides the shape has. The prefixes, such as quad-, penta-, hexa-, come from greek numbers to show the number of sides.
• Is anything with four "equal" sides a rhombus?
• shares propertys of both rhombus and rectangle!1