Density

Use a triangle area formula that works when the height is unknown. The eighth installment in a 16-part series on trigonometry revisits the trigonometric triangle area formula that previously was shown to work with the acute triangles....

Pupils visualize distance-rate-time problems by using bar models. The lesson presents examples of four different types of rate problems and shows how they can be solved using bar models and equations. Each example is followed...

Here are five different versions of worksheets to calculate percentages of a number. Although there is no answer key, this resource takes the work out of making different versions of the same topic.

Use more than one whole to solve percent problems. The ninth installment in a 20-part series has pupils work percent problems in which they must determine two wholes. Individuals use double number lines to represent and solve the...

Need an activity for teaching the Pythagorean Theorem? Geometry juniors apply the Pythagorean theorem to two triangles to determine a final calculation. 

Try five problems on triangles. Levels A and B focus on shapes that can be created from right triangles. Level C touches upon the relationship between the area of a six-pointed star and the area of each triangle of which it is composed....

Change the density of water by adding minerals. The presentation discusses density—from the definition to calculations—and applies it to the real world. It briefly mentions specific gravity, and finishes by showing Archimedes'...

While the lesson focuses on right triangles, this activity offers a great way to practice the area of all triangles through an interactive webpage. The activity begins with the class taking a square paper and cutting in in half; can they...

Determine whether it is right or not. Using the Pythagorean Theorem, the video shows how to determine whether a triangle is a right triangle. Pupils practice the skill in a few of the problems in the associated worksheets on the...

When does the Pythagorean Theorem come in handy? An intriguing video uses the Pythagorean Theorem to solve problems other than simply finding the length of a side of a right triangle. Pupils find the diagonal of a rectangle and the...