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Activity
Illustrative Mathematics

Reflections and Isosceles Triangles

For Teachers 9th - 11th Standards
Geometers explore symmetries of isosceles triangles by using rigid transformations of the plane. They complete four tasks, including congruence proofs, which illustrate the relationship between congruence and rigid transformations. The...
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Worksheet
Curated OER

Triangle worksheets

For Students 10th
In this geometry worksheet, 10th graders explore triangle properties, including the sum of the measures of the angles of a triangle, the triangle inequalities, properties of isosceles triangles, properties of congruent triangles, and...
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Worksheet
Curated OER

Triangles and Congruence

For Students 8th - 10th
Can your class construct triangles and determine congruence? Find out with this well put together worksheet. THey construct triangles to given specifications and identify if they are congruent. There are 3 muti-step problems to solve.
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Assessment
Inside Mathematics

Circles in Triangles

For Teachers 9th - 12th Standards
Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...
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Handout
Mt. San Antonio Collage

Congruent Triangles Applications

For Students 9th - 12th Standards
Triangles are all about threes, and practicing proving postulates is a great way to get started. The first page of the worksheet provides a brief introduction of the different properties and postulates. The remaining pages contain...
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Worksheet
Geometry Accelerated

Accelerated Geometry Review Sheet

For Students 8th - 10th Standards
Your geometry learners use their knowledge of various geometric concepts to write proofs. Starting with givens containing parallel line segments with transversals and triangles and quadrilaterals, and the mid-point and distance formulas;...
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Worksheet
Curated OER

Coordinate Geometry Proofs

For Students 10th
In this coordinate geometry worksheet, 10th graders solve and draw 10 different problems related to complete proofs in coordinate geometry. First, they prove that a figure with given points is another figure by using slopes. Then,...
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Worksheet
Curated OER

Proofs

For Students 8th - 11th
In this geometric proof worksheet, students compose 20 triangle congruency proofs. Students will decide if there is enough information in problems 1-6 to prove if any triangles are congruent. In problems 17 to 20, students use given...
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Worksheet
Mt. San Antonio Collage

The Trapezoid

For Students 9th - 12th Standards
Enjoy this nicely organized worksheet that puts together multiple problems regarding trapezoid proofs. The resource can be used as a guide that begins with proving properties and ends with solving for measures of line segments.
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Worksheet
Curated OER

Trapezoids

For Students 10th
For this trapezoids worksheet, 10th graders solve 5 different problems related to trapezoids and applying the appropriate theorem. First, they define a trapezoid, including its bases, legs, and base angles. Then, students use the...
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Worksheet
Curated OER

Triangle Proofs

For Students 9th - 12th
In this triangle proofs activity, students answer 5 questions about triangles and polygons given certain information. Students then construct 4 triangle or polygon proofs.
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Assessment
Inside Mathematics

Hopewell Geometry

For Teachers 9th - 12th Standards
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
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Lesson Plan
Curated OER

Worksheet 7: Slope and Tangents

For Teachers 12th - Higher Ed
Providing both review and practice problems, this worksheet prompts students to answer five questions having to do with slope, tangents lines, graphing, the Squeeze Theorem, differentiable functions and derivatives. This activity could...
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Lesson Plan
Curated OER

Proposed Problems

For Teachers 11th - Higher Ed
In this math worksheet, students read the information about an isosceles triangle. The ratio of the lengths of two sides is equal. They determine the exact measures of its angles.
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Activity
Curated OER

Inscribing a Square in a Circle

For Teachers 9th - 11th Standards
Inscribing a square in a circle brings up a number of interesting geometry topics including triangle congruence and how to prove a quadrilateral is a square. This activity is followed up by finding the area of the square and determining...
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Worksheet
Curated OER

Midpoints

For Students 10th
In this midpoints instructional activity, 10th graders solve and complete 10 different problems. First, they find the perimeter of each illustrated triangle. Then, students determine the bases and median of a trapezoid. They also prove...
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Worksheet
Curated OER

Proofs in Coordinate Geometry

For Students 10th - 11th
In this coordinate geometry activity, students identify the lengths of a quadrilateral and find the slope of a line. They use proofs to identify the characteristics of given quadrilaterals. This one-page activity contains ten problems.