Illustration of 3 equal dihedral angles. "Two dihedral angles have the same ratio as their plane angles."

Equal Dihedral Angles

Illustration of 3 equal dihedral angles. "Two dihedral angles have the same ratio as their plane angles."

Bag with four white, four striped, and two black marbles used for a probability activity.

Bag with Ten Marbles

Bag with four white, four striped, and two black marbles used for a probability activity.

Bag with four white, three black, and three striped marbles used for a probability activity.

Bag with Ten Marbles

Bag with four white, three black, and three striped marbles used for a probability activity.

Bag with four striped, three black, and three white marbles used for a probability activity.

Bag with Ten Marbles

Bag with four striped, three black, and three white marbles used for a probability activity.

Bag with four black, four white, and two striped marbles used for a probability activity.

Bag with Ten Marbles

Bag with four black, four white, and two striped marbles used for a probability activity.

Bag with four black, three white, and three striped marbles used for a probability activity.

Bag with Ten Marbles

Bag with four black, three white, and three striped marbles used for a probability activity.

Bag with four black, four striped, and two white marbles used for a probability activity.

Bag with Ten Marbles

Bag with four black, four striped, and two white marbles used for a probability activity.

Circle with triangle to show how to divide a line in extreme and mean ratio.

Circle and Triangle

Circle with triangle to show how to divide a line in extreme and mean ratio.

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane. The circle is divided into four quadrants by the x- and y- axes. The circle can be labeled and used to find the six trigonometric values (sin, cos, tan, cot, sec, csc, cot) at each of the quadrantal angles.

Unit Circle

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane. The…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. All quadrantal angles are given in radian measure in terms of pi.

Unit Circle Labeled At Quadrantal Angles

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. All quadrantal angles and angles that have reference angles of 30°, 45°, and 60° are given in radian measure in terms of pi. At each quadrantal angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled At Special Angles

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. All quadrantal angles and angles that have reference angles of 30°, 45°, and 60° are given in radian measure in terms of pi.

Unit Circle Labeled At Special Angles

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. At 30° increments, the angles are given in both radian and degree measure. At each angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled In 30° Increments With Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. The circle is marked and labeled in both radians and degrees in 45° increments. At each angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled In 45 ° Increments

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. At 45° increments, the angles are given in both radian and degree measure. At each quadrantal angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled In 45° Increments With Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. At 45° increments, the angles are given in both radian and degree measure. At each angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled In 45° Increments With Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane. All quadrantal angles are given in radian measure in terms of pi.  At each angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled With Quadrantal Angles And Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane. All…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. All quadrantal angles are given in degree measure. At each angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled With Quadrantal Angles And Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. All quadrantal angles are given in both radian and degree measure. At each angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled With Quadrantal Angles And Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane. At each quadrantal angle, the coordinates are given, but not the angle measure. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled With Quadrantal Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane. At each…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. At each quadrantal angle, the coordinates are given, but not the angle measure. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled With Quadrantal Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. The circle is marked and labeled in radians. All quadrantal angles and angles that have reference angles of 30°, 45°, and 60° are given in radian measure in terms of pi. At each angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled With Special Angles And Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. The circle is marked and labeled in both radians and degrees at all quadrantal angles and angles that have reference angles of 30°, 45°, and 60°. At each angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled With Special Angles And Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. The circle is marked and labeled in both radians and degrees at all quadrantal angles and angles that have reference angles of 30°, 45°, and 60°. At each angle, the coordinates are given. These coordinates can be used to find the six trigonometric values/ratios. The x-coordinate is the value of cosine at the given angle and the y-coordinate is the value of sine. From those ratios, the other 4 trigonometric values can be calculated.

Unit Circle Labeled With Special Angles And Values

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with…

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane. All quadrantal angles and angles that have reference angles of 30°, 45°, and 60° are marked from the origin, but no values are given.

Unit Circle Marked At Special Angles

Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane. All…

Illustration of equal circles to show that two central angles have the same ratio as their intercepted arcs.

Equal Circles With Intercepted Arcs

Illustration of equal circles to show that two central angles have the same ratio as their intercepted…

Illustration of 2 right circular cones that are similar.

2 Similar Right Circular Cones

Illustration of 2 right circular cones that are similar.

Illustration of 2 similar cylinders. The height and diameter of the smaller cylinder is half that of the larger one.

2 Similar Cylinders

Illustration of 2 similar cylinders. The height and diameter of the smaller cylinder is half that of…

Illustration of 2 soup cans that are similar cylinders. The diameter and height of the smaller can is one half that of the larger.

2 Soup Can Cylinders

Illustration of 2 soup cans that are similar cylinders. The diameter and height of the smaller can is…

Illustration of 3 similar cylinders. The height and diameter in each successively smaller cylinder is 1/2 that of the previous one.

3 Similar Cylinders

Illustration of 3 similar cylinders. The height and diameter in each successively smaller cylinder is…

Illustration of 3 similar cylinders. The height and diameter in each successively smaller cylinder is one half that of the previous one.

3 Similar Cylinders

Illustration of 3 similar cylinders. The height and diameter in each successively smaller cylinder is…

Illustration of half of an ellipse. "The ordinates of two corresponding points in an ellipse and its auxiliary circle are in the ratio b:a."

Corresponding Points in an Ellipse and Circle

Illustration of half of an ellipse. "The ordinates of two corresponding points in an ellipse and its…

Illustration of an extension ladder. If ladder is leaned against a building, it will form a right triangle with the ground.

Extension Ladder

Illustration of an extension ladder. If ladder is leaned against a building, it will form a right triangle…

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned toward a building, it will form the hypotenuse of a right triangle.

Leaning Ladder

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned…

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned toward a building, it will form the hypotenuse of a right triangle.

Leaning Ladder

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned…

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned toward a building, it will form the hypotenuse of a right triangle.

Leaning Ladder

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned…

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned toward a building, it will form the hypotenuse of a right triangle.

Leaning Ladder

Illustration of a ladder that is not perpendicular to the ground. If it is set on the ground and leaned…

Illustration of a ladder leaning against the side of a building (wall) to form a right triangle .

Ladder Leaning Against a Building

Illustration of a ladder leaning against the side of a building (wall) to form a right triangle .

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a right triangle .

Ladder Leaning Against a Tree

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a…

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a right triangle .

Ladder Leaning Against a Tree

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a…

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a right triangle .

Ladder Leaning Against a Tree

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a…

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a right triangle .

Ladder Leaning Against a Tree

Illustration of a ladder leaning against a palm tree, that is perpendicular to the ground, to form a…

Illustration of 2 ladders leaning against opposite sides of a palm tree to form similar right triangles. The angles of elevation from the ground to where the ladders meet the tree are congruent. Illustration can be used for problems involving proportions.

2 Ladders Leaning Against a Tree

Illustration of 2 ladders leaning against opposite sides of a palm tree to form similar right triangles.…

Illustration of 3 ladders leaning against the side of a building (wall) to form right triangles. The distance from the base of the ladders to the wall is the same for all three ladders.

3 Ladders Leaning Against a Wall

Illustration of 3 ladders leaning against the side of a building (wall) to form right triangles. The…

Illustration of a lever with fulcrum F. W represents the weight lifted, P is the force that does the lifting, D is the distance from the fulcrum to the point of application of the force, and d is the distance from the fulcrum to the point where the weight is attached. In all possible relations of the fulcrum, weight, and force the following proportion holds: P:W = d:D.

Lever and Fulcrum

Illustration of a lever with fulcrum F. W represents the weight lifted, P is the force that does the…

Illustration of a hammer being used as a lever. F represents the fulcrum.

Hammer Used as a Lever

Illustration of a hammer being used as a lever. F represents the fulcrum.

Illustration of an ordinary steel-yard being used as a lever. F represents the fulcrum. Weight P is used to balance weight W.

Steel-yard Used as a Lever

Illustration of an ordinary steel-yard being used as a lever. F represents the fulcrum. Weight P is…

Illustration of two straight lines that can be used to find ratios.

Straight Lines to Find Ratios

Illustration of two straight lines that can be used to find ratios.

Illustration of a hydraulic machine. "A principle known as Pascal's Law states that pressure exerted on a liquid in a closed vessel is transmitted equally and undiminished in all directions." If a, A, p, and P respectively represent the areas and pressures, then the following proportion holds: a:A = p:P.

Hydraulic Machine Exerting Pressure

Illustration of a hydraulic machine. "A principle known as Pascal's Law states that pressure exerted…

Illustration of 2 right rectangular prisms. The bases are congruent, but the height of the smaller prism is one half that of the larger. Hidden edges are shown.

2 Rectangular Prisms

Illustration of 2 right rectangular prisms. The bases are congruent, but the height of the smaller prism…

Illustration of 2 right rectangular prisms. The bases are congruent, but the height of the smaller prism is one half that of the larger.

2 Rectangular Prisms

Illustration of 2 right rectangular prisms. The bases are congruent, but the height of the smaller prism…

These pulleys are grooved such as to guide the inner belt, in this system there is less of a chance that a belt will run out of the pulley.

Grooved Pulleys

These pulleys are grooved such as to guide the inner belt, in this system there is less of a chance…

Illustration of a leaning tower with a perpendicular drawn from the top of the tower to the ground to form a right triangle.

Leaning Tower

Illustration of a leaning tower with a perpendicular drawn from the top of the tower to the ground to…

Illustration of a palm tree that is perpendicular to the ground. The tree is perfectly straight, as is the ground. This drawing could be used for shadow, proportion, trigonometric, or Pythagorean Theorem problems.

Palm Tree Perpendicular to Ground

Illustration of a palm tree that is perpendicular to the ground. The tree is perfectly straight, as…

"...the mechanical advantage of this machine (wheel and axle) equal the ratio between the radii, diameters, or circumferences of the wheel and of the axle." -Avery 1895

Wheel and Axle with Rope and Bucket

"...the mechanical advantage of this machine (wheel and axle) equal the ratio between the radii, diameters,…