Radford University
Finding a Location for Your Kitchen Island
Where is the best place to work? Small groups map out a kitchen on a coordinate plane and find the centers of the work triangle to find the best place to install an island. The teams use algebraic methods to locate the center by finding...
Mathematics Vision Project
Geometric Figures
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...
Curated OER
Medians and Altitudes of Triangles
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 problems. Answers...
Curated OER
Regents Exam Questions G.G.21: Centroid, Orthocenter, Incenter, and Circumcenter
In this triangles instructional activity, students solve 4 multiple choice problems. Students find the centroid, orthocenter, incenter, and circumcenter or various triangles.
Curated OER
Exploring the Orthocenter of a Triangle
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...
Curated OER
Properties of the Centers of a Triangle
High schoolers investigate properties of the four centers of a triangle and explore a special property of the circumcenter and orthocenter of a triangle. This lesson requires the use of Cabri, Jr.
Curated OER
Concurrence
In this concurrence activity, 10th graders solve 10 different problems related to determining various concurrences. First, they determine which type of triangle has two altitudes outside of it. Then, students determine the distance...