Finding Areas of Triangles, Rectangles, and Circles

A triangle, square, hexagon, and circle all have a perimeter of one unit. Eighth graders must attempt to find the area of each and arrange them in order from least to greatest areas. A terrific task for applying four different...

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

The measurements are all in the can. The review for the math portion of the General Certificate of Secondary Education assessments provides scholars the opportunity to review finding volume and surface area of a cylinder. Pupils work on...

This lecture explores finding the area of each of the triangles created by drawing two diagonal lines through a rectangle. It provides a detailed explanation of how to use a formula to solve the given problem. Tip: Use this for test...

While the instructional activity 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...

Don't believe everything that you hear — make them prove it! The video shows two methods to prove the Triangle Angle Sum Theorem. The following two videos apply the theorem to finding missing angle measures.

The teacher explains how the formula for a triangle was determined. It is related to a parallelogram. What? The formula for the area of a triangle is derived from the area of a parallelogram? Seeing is believing, so watch this video to...

Get lost in the classifications. Using the backdrop of the Bermuda Triangle, pupils classify it by angle and side measures. They also learn information about the triangle and its history.

Learn how to use the formula for area to solve a problem about a rectangle. The demonstrator shows how to plug in the known values of a rectangle, and then how to use the formula for area to solve for the variable in question.

Area=Length x Width. Locate the value of the length of the rectangle and locate the given width and plug them in to solve. Don't forget to include the units and multiply them too.