Curated OER
Investigating Segments in a Right Triangle
High schoolers explore the concept of right triangles as they construct a right triangle using Cabri Jr. Learners find the midpoint of the hypotenuse and construct a line from the midpoint to the vertex of the right angle. They then...
Curated OER
Congruent Triangles
Students identify properties of triangles. In this geometry lesson, students differentiate between similar and congruent triangles. They use the umber of sides to help define the angle of the polygon.
Curated OER
Nested Similar Triangles
Nested triangles have been created so that they share a common vertex and vertex angle. Learners drag the endpoints of the side that is opposite the common angle to discover the conditions that make the nested triangles similar. When...
Curated OER
Circumscribing a Circle About a Triangle
Pupils circumscribe a circle about a triangle. They construct a triangle using Cabri Jr and then circumscribe it. They then use knowledge of perpendicular bisectors and circumcenters to locate the center of the circle and then...
Curated OER
Triangle Trigonometry IB Packet
In this trigonometry worksheet, students use triangle trignometry to solve problems in order to find the missing length, angle, or area of the triangle. The one page worksheet contains five ...
Curated OER
Triangle Sum Theorem
Teach your class how to solve problems using the triangle sum theorem. In this geometry lesson, students identify the missing angles in a triangle using the sum theorem. They graph triangles on the TI and moves the sides around to create...
Curated OER
30-60-90 Right Triangles in Cabri Jr.
Young mathematicians draw and label right triangles using Cabri Jr. technology. They create other special right triangles and identify the length of the hypotenuse and each leg. High schoolers explore the ratios to determine how the...
Illinois State Board of Education
Geoboard Areas
Middle school geometers determine the area of a shape on a geoboard or dot paper and draw figures that meet given area conditions. Working as a class, they develop and discuss various ways to draw geometric shapes with specified...
Curated OER
Ratios in Right Triangles
Learners calculate the sides of right triangles in this trigonometric ratios lesson. They use Cabri Jr. software and TI-83 or TI-84 calculators to find the side lengths and their ratios to each other for various triangles. The provided...
Curated OER
Midsegments of Quadrilaterals
High schoolers explore the concept of quadrilaterals as they find the midsegments of quadrilaterals using Cabri Jr. on a graphing calculator. They find midpoints, slopes, angles, and distances of lines and angles.
Mathematics Vision Project
Circles: A Geometric Perspective
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...
Curated OER
Areas of triangles, trapezoids, and rhombi
Students solve geometry problems. In this area and perimeter instructional activity, students use formulas to solve problems from the textbook.
Curated OER
Areeas of Parallelograms and Triangles
Twelfth graders are able to deduce the area of polygons by using several methods such as coordinate method. They are able to apply the area of polygons to real life situations. Students apply the Pythagorean Theorem in problem solving...
Curated OER
Review of Triangles
Students investigate the Pythagorean Theorem. In this geometry instructional activity, students define angles and sides of right triangles. They calculate the area and surface area using formulas derived by the Pythagorean Theorem.
Curated OER
Triangles
In this triangles worksheet, 10th graders solve 10 different problems that include determining the measurement of various angles. First, they determine the area of a triangle illustrated on the sheet. Then, students use the picture to...
Curated OER
Review Geometry - Week 8 (Triangles)
In this triangle worksheet, students use similar figures to find the length of one side of two similar triangles. They find the area of a triangle inscribed in a rectangle. This two-page worksheet contains eight problems.
Curated OER
Seven Sets of Area Problems
For this area worksheet, students solve for the area of rectangles, parallelograms, triangles, trapezoids, kites, regular polygons, circles, and surface area. The worksheets is divided into seven different sets of problems.
Curated OER
Perimeter and Area
Seventh graders develop strategies for finding the perimeter and area of large geometric figures. Through lecture and guided practice, 7th graders practice the strategy of dividing a geometric shape into smaller more manageable shapes...
Curated OER
Chapter 8 Extra Problems Worksheet: Similar Triangles
For this similar triangles worksheet, students solve 6 similar triangles. Students use proportions to solve similar triangles and similar rectangles.
Curated OER
Interior and Exterior Angles of Polygons
For this angles of polygons worksheet, 10th graders solve and complete 18 different problems that include determining various interior and exterior angles. First, they determine the measure of various angles described in the first half...
Curated OER
Area and Perimeter of Compound Shapes
In this geometry worksheet, students find the area and perimeter of 6 different compound shapes containing squares, rectangles, triangles, and half circles.
Curated OER
Area and Perimeter of Polygons
In this geometry worksheet, 10th graders calculate the perimeter and area using the specific formula for that polygon. There are 5 questions with an answer key.
Curated OER
Triangle Explorer
Students calculate the area of triangles using a variety of materials including computer applets.
Concord Consortium
Three Rubber Bands
Stretch your mind about triangles. Given a triangle, scholars consider a smaller triangle formed when they stretch three rubber bands from each vertex to the opposite side. They determine the ratios of the areas and perimeters of the...