Teachers Lesson Plans

Seeing Math in Art

Acute Angle
Acute Angle
Definition: An angle measuring less than 90 degrees.

Area of a Circle
Area of a Circle
Definition: The amount of space inside a circle, measured in square units, and calculated by the formula A = πr2.

Circle
Circle
Definition: A two-dimensional shape whose circumference (perimeter) is always the same distance from the centre (this line is called the radius).

Circumference
Circumference
Definition: The distance (also known as the perimeter) around a circle, and calculated by the formula C = πd.

Concentric
Concentric
Definition: Having a common center, as circles of different size, one within another.

Congruent
Congruent
Definition: Having the same shape, size, and angles ? geometrically equal.

Diameter
Diameter
Definition: A straight line passing through the centre of a circle to touch both sides of the circumference.

Factorial
Definition: The product of a whole number multiplied by every whole number between itself and 1, written using the notation n!.

Fractal
Fractal
Definition: A geometric figure that is called self-similar. One way to understand this is that the shape of the fractal repeats the same pattern within itself when it is enlarged.

Image: Kazuo Nakamura Number Structure and Fractals, 1983
no. 39855


Horizontal
Horizontal
Definition:

Parallel to the horizon.

Image: Jean Paul Lemieux, The Noon Train, 1956
no. 6913


Hypotenuse
Hypotenuse
Definition: The longest side in a right-angled triangle. This side is always opposite the right angle.

Isosceles Triangle
Isosceles Triangle
Definition: A triangle with two equal sides and two equal angles.

Net
Net
Definition: The flat shape which can be folded up or bent into a three-dimensional shape (shell).

Permutation
Permutation
Definition: An arrangement or rearrangement of the elements in an ordered list, determined by factorials and written using the notation nPr=n!/r!.

Pythagorean Theorem
Pythagorean Theorem
Definition: The area of the square built upon the hypotenuse of a right-angled triangle is equal to sum of the areas of the squares upon the other two sides (legs). Algebraically, for a triangle with legs a and b, and hypotenuse c, this means a2 + b2 = c2.

Pythagorean Triple
Pythagorean Triple
Definition: A set of three positive integers a, b, and c, such that a right-angled triangle exists with legs a, b, and hypotenuse c. Another way of saying this is that there are three positive numbers a, b, c that satisfies Pythagorean Theorem.

Radius (pl. Radii)
Radius (pl. Radii)
Definition: The distance from the centre of a circle to its circumference.

Right Angle
Right Angle
Definition: An angle measuring 90 degrees.

Right Prism
Right Prism
Definition: A three-dimensional shape with two identical parallel bases, with all other faces as rectangles.

Similar
Similar
Definition: Having the same shape, but not the same size; having the same angle measurements, but not the same length measurements, but are in proportion.

Surface Area
Surface Area
Definition: The total area of the surface of a three-dimensional shape, measured in square units.

Transformation
Definition: A change in position or size, including a reflection, translation, rotation, or dilatation.

Translation
Translation
Definition: The transformation of an item in any direction without rotating it or changing its geometric properties.

Vertical
Vertical
Definition:

At right angles, 90°, to the horizon.

Image: Barnett Newman Voice of Fire, 1967
© Estate of Barnett Newman / ARS (New York) / SODRAC (Montréal)
no. 30502


Volume
Volume
Definition: The amount of space occupied by an object, measured in cubic units.