Math Madness
Most recently we've been discussing a line of symmetry,
2-D and 3-D shapes, and arrays.
A line of symmetry is a line that divides a figure into
two equal (congruent) halves. It is a mirror image.
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- A figure can have more than
- one line of symmetry.
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2-Dimensional Shapes
(including polygons)
Having the dimensions of height and width only.
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3-Dimensional Shapes
or Geometric Solids
Having the dimensions of height, width, and depth.
Vocabulary: edges, vertices, faces
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Array
A rectangular arrangement of objects in rows and columns.
This is the foundation for multiplication.
This is a 2 by 6 array.
You can read it as:
2 groups of 6
2 rows of 6
2 multiplied by 6
2 times 6
2 by 6
The multiplication number model would be:
2 X 6 = 12
The addition number model would be:
6 + 6 = 12
We are beginning to use arrays to help us
solve multiplication story problems.
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