Illustration of circle with inscribed angle 30 and central angle 60.

Inscribed and Central Angles 30 60

Illustration of circle with inscribed angle 30 and central angle 60.

Groups of change with totals from 1 to 100 cents using the least amount of coins.

30 Cents

Groups of change with totals from 1 to 100 cents using the least amount of coins.

Illustration of three circles enclosed in an equilateral triangle.

Circles Enclosed in Equilateral Triangle

Illustration of three circles enclosed in an equilateral triangle.

An illustration of a Roman Numeral clock showing 2:30.

Clock 2:30

An illustration of a Roman Numeral clock showing 2:30.

Illustration of 30 congruent cubes stacked in decreasing heights. A 3-dimensional representation on a 2-dimensional surface that can be used for testing depth perception and identifying and counting cubes, edges, and faces.

30 Stacked Congruent Cubes

Illustration of 30 congruent cubes stacked in decreasing heights. A 3-dimensional representation on…

An illustration of a pyramid with the top cut off by a plane parallel to the base. The remaining part is called a frustum. This frustum has right triangular bases, one with 20 inch side and the other with a 30 inch side. Height is 27 inches.

Pyramid Frustum With Triangular Bases and Height of 27 inches

An illustration of a pyramid with the top cut off by a plane parallel to the base. The remaining part…

30-60-90 Right Triangle

Triangle 30-60-90

30-60-90 Right Triangle

30-60-90 right triangle.

30-60-90 Right Triangle

30-60-90 right triangle.

An isosceles triangle with angles 120, 30, 30

Isosceles Triangle degrees 120, 30, 30

An isosceles triangle with angles 120, 30, 30

An isosceles triangle with angles 30, 75, 75

Isosceles Triangle degrees 30, 75, 75

An isosceles triangle with angles 30, 75, 75

Trigonometric reference triangles/angles drawn for 60 degree reference angel in quadrants I and II.

Trigonometric Reference Triangles/Angles (60 degrees) Drawn in Quadrants

Trigonometric reference triangles/angles drawn for 60 degree reference angel in quadrants I and II.

Special right triangle with angles 30 degrees, 60 degrees, and 90 degrees with side measures/relationships shown.

Special Right Triangle with Angles 30, 60, 90 degrees

Special right triangle with angles 30 degrees, 60 degrees, and 90 degrees with side measures/relationships…

Steam pipe illustration of 30-60-90 triangle.

Triangle Steam Pipe

Steam pipe illustration of 30-60-90 triangle.