Worksheet
Curated OER

Geometry: Calculating Areas of Triangles

For Students 4th - 7th
For this geometry worksheet, students calculate the areas for each of the eight triangles shown and write their answers on the lines provided.
Lesson Plan
Curated OER

Finding The Area Of Shapes

For Teachers 4th
Fourth graders investigate the concept of computing the area using different shapes. They use prior knowledge in order to devise a formula for a parallelogram. Scaffolding is provided by the teacher to find the formula of area for...
Lesson Plan
Curated OER

How To Find the Area of a Square And Rectangle

For Teachers 4th - 6th
Learners practice using the formula to calculate the area of a square or triangle. They participate in large group guided practice using simple area of squares problems then complete a series of problems calculating the area of rectangles.
Lesson Plan
Curated OER

Finding the Area of a Parallelogram with Translations

For Teachers 8th - 10th
Students calculate the area of parallelograms. In this geometry lesson, students identify properties of parallelograms and use to to solve problems. They create polygons using Cabri software.
Worksheet
Curated OER

Find the Area or Missing Length of the Polygon

For Students 7th - 10th
For this area and perimeter worksheet, students find the length or area of seventeen figures.  The figures examined are triangles, trapezoids, parallelograms, rectangles, and hexagons.  Some examples and solutions are...
Lesson Plan
Curated OER

Area Measures and Right Triangles

For Teachers 9th - 12th Standards
Your class will investigate the relationship among different triangles. This geometry lesson, demonstrates how to make a connection between triangles and the Pythagorean Theorem. They identify the missing side or angle of a triangle.
Lesson Plan
Curated OER

Flip's Flag

For Teachers 5th
Fifth graders apply the symmetry and angle properties of polygons and use fractions to express the relationships between the areas of rectangles, squares, and triangles. They analyze various country flags and develop mathematical...
Lesson Plan
Curated OER

Exploring the Circumcenter of a Triangle

For Teachers 9th - 12th Standards
Students construct the circumcenter of a triangle. For this constructing the circumcenter of a triangle lesson, students construct a triangle using Cabri Jr. Students draw perpendicular bisectors of the sides of the triangle. Students...
Lesson Plan
Curated OER

Measuring Angles in a Triangle

For Teachers 9th - 12th Standards
High schoolers investigate the sum of the measures of the angles of a triangle. They draw a triangle and measure the interior angles. Using Cabri Jr., learners find the sum of the measures of the interior angles. The activity provides an...
Lesson Plan
Curated OER

Triangle Midsegment

For Teachers 9th - 12th Standards
Learn how to calculate the length and midsegments of triangles. Students differentiate between similar and congruent triangles. They create a spreadsheet with their findings.
Lesson Plan
Curated OER

Investigating Segments in a Right Triangle

For Teachers 9th - 12th Standards
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...
Lesson Plan
Curated OER

Exploring the Orthocenter of a Triangle

For Teachers 9th - 12th Standards
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...
Worksheet
Curated OER

Area of Triangles

For Students 10th
In this geometry worksheet, 10th graders calculate the area of right triangles using the Pythagorean Theorem combined with the area formula. There are 14 questions with an answer key.
Lesson Plan
Curated OER

Circumscribing a Circle About a Triangle

For Teachers 9th - 12th Standards
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...
Lesson Plan
Curated OER

Nested Similar Triangles

For Teachers 9th - 12th Standards
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...
Lesson Plan
Curated OER

Midsegments of a Triangle

For Teachers 9th - 12th Standards
Students analyze midsegments of triangles in this instructional activity. They use Cabri Jr. software to observe the relationships between interior angles and midsegments of triangles. Specific instructions for creating this...
Lesson Plan
Curated OER

Triangle Sum Theorem

For Teachers 9th - 12th Standards
Teach your class how to solve problems using the triangle sum theorem. In this geometry instructional activity, students identify the missing angles in a triangle using the sum theorem. They graph triangles on the TI and moves the sides...
Lesson Plan
Curated OER

30-60-90 Right Triangles in Cabri Jr.

For Teachers 9th - 12th Standards
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. Young scholars explore the ratios to determine how the...
Interactive
Curated OER

Area of Figures That Include Circles

For Students 10th - 12th
In this area worksheet, students calculate the perimeter and area of given complex figures.  They determine the area of shaded regions, and find the distance between straight lines.  This one-page worksheet contains 4...
Lesson Plan
Curated OER

Ratios in Right Triangles

For Teachers 9th - 12th Standards
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...
Assessment
Concord Consortium

Divisions

For Students 7th - 12th Standards
Divide and conquer the geometry problem. Young scholars consider how to subdivide triangles into smaller ones that have equal areas. They must apply their knowledge of medians to help accomplish the task.
Assessment
EngageNY

End-of-Module Assessment Task: Pre-Calculus Module 4

For Students 11th - 12th Standards
Challenge your scholars to show what they know about the Law of Sines, Law of Cosines, and inverses. The six-question assessment is the last in a series of 16. Pupils find the area of triangles and show that the Law of Sines and Law of...
Worksheet
Curated OER

Chapter 8 Extra Problems Worksheet: Similar Triangles

For Students 9th - 12th
In this similar triangles worksheet, students solve 6 similar triangles. Students use proportions to solve similar triangles and similar rectangles.
Worksheet
Curated OER

Area

For Students 7th - 8th
In this area worksheet, students solve and complete 20 different problems that include the measurement of various figures. First, they determine the area of each of the triangles, parallelograms and trapezoids. Then, students determine...