Under which conditions can a triangle be classified as isosceles? High schoolers practice identifying isosceles triangles and special line segments, including angle bisectors, medians of triangles, and perpendicular bisectors of sides of...

The problem seems simple: find the area of the equilateral triangle whose sides are each length 1. In fact, this same problem is solved in 8th grade, addressing a different Common Core standard, using the formula for area of a triangle...

Starting with similar triangles and dilation factors, this unit quickly and thoroughly progresses into the world of right triangle features and trigonometric relationships. Presented in easy-to-attack modules with copious application...

This is a good model for learners to visualize triangles of the same base and height. They can can begin to comprehend that these triangles will have the same area no matter how the triangle is drawn. It is part of a series of resources...

Medians, midsegments, altitudes, oh my! Pupils study the properties of the median of a triangle, initially examining a proof utilizing midsegments to determine the length ratio of a median. They then use the information to find missing...

In this geometry worksheet, students differentiate between regular triangles and isosceles triangles. They apply the converse theorem and the vertex angle. There are eleven questions with an answer key.

In this geometry worksheet, 10th graders determine if a given segment is a median or altitude of a triangle and use then find the indicated missing length or equation of a line.  The two page worksheet contains twenty...

Can your class solve right triangles and identify the properties common to right triangles? They will investigate and state the relationship between the altitude to the hypotenuse and the two segments of the hypotenuse formed by the...

Learners identify important properties of triangles. In this geometry lesson, students differentiate between medians, bisectors and altitudes in a triangle. They identify the properties of these important segments.

What do you do when you don't think you have enough information? You look for another way to do the problem! Pupils combine what they know about finding the area of a triangle and trigonometry to determine triangle area when they don't...

In this geometry worksheet, students construct angles and identify medians and altitudes. They use a compass and protractor to perform heir construction. There are 28 questions.

Students calculate the height and altitude of a pyramid. In this geometry activity, students define the parts that make up a pyramid. They use the Pythagorean Theorem to find the missing parts of a pyramid.

In this triangles worksheet, 10th graders solve 3 extensive informal geometry problems that involve triangles. First, they sketch a triangle, selecting 3 of the sides and constructing 3 midpoints. Students then draw each of 3 medians by...

Why are right triangles so special? Pupils begin their study of right triangles by examining similar right triangles. Verifying through proofs, scholars recognize the three similar right triangles formed by drawing the altitude. Once...

Logical thinking is at the forefront of this jam-packed lesson, with young mathematicians not only investigating geometric concepts but also how they "know what they know". Through each activity and worksheet, learners wrestle with...

Middle and high schoolers investigate all the different places in math that square root is present. In this geometry lesson, pupils discuss square roots as it relates to a right triangle and construction. They go over altitude, rise,...

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...

Four triangles are depicted for learners to construct on a geoboard. They compute and compare the areas, and so meet one of the sixth grade Common Core standards for geometry. Note that the set of triangles does not include a right...

Use this lengths of horizontal and vertical line segments practice activity to have learners sharpen their problem solving skills as they solve six story problems.

Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems. 

Transform pupils into mathematicians as they create their own definitions and formulas. Scholars examine an assortment of triangles and create a definition and formula for determining the sharpness of the vertex angle. The groups of...

In this geometry worksheet, 10th graders review the vocabulary associated with the special segments of a triangle and the associated points of concurrency and solve problems in which they find the indicated missing angle or...

Young mathematicians explore the concept of triangles as they construct altitudes of triangles to find the orthocenter. Learners construct their triangles using Cabri Jr. on their graphing calculators and find that the altitudes of a...

Prove the Law of Sines two ways. The ninth segment in a series of 16 introduces the Law of Sines to help the class find lengths of sides in oblique triangles. Pupils develop a proof of the Law of Sines by drawing an altitude and a second...