+
Interactive
Curated OER

Mixed Right Triangles

For Students 10th
In this geometry worksheet, 10th graders use right triangle trigonometry to find the missing angle measure or side length in right triangles. The one page interactive worksheet contains ten questions. Answers and hints are included. 
+
Worksheet
Curated OER

Functions of Triangles

For Students 11th - Higher Ed
For this math worksheet, students find the functions for each of the triangles. Then they determine the reference angles from standard position.
+
Assessment
Concord Consortium

Proportional Representation

For Students 9th - 12th Standards
Sometimes the solution is all a matter of perspective. The short assessment task presents a problem to pupils that requires them to make sense of a diagram. Once learners see two similar triangles, the rest of the solution is solving a...
+
Handout
2
2
Curated OER

Trig Cheat Sheet

For Teachers 10th - 12th Standards
Your pre-calculus learners will make use of this wonderful cheat sheet that summarizes all things trigonometric. Definitions based on both the unit circle and the right triangle are included, as well as many convenient trigonometric...
+
Worksheet
Lane Community College

Review Sheets: Geometry

For Students 8th - 11th
Full of problems with polygons, angles, lines, and triangles, your learners get a multi-page packet that provides all they need to know. It contains many of the standard problem types as well as some more challenging questions. 
+
Unit Plan
Mathematics Vision Project

Geometric Figures

For Teachers 10th - 12th Standards
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...
+
Lesson Plan
Curated OER

Perpendicular and Angle Bisectors

For Teachers 10th
In this geometry worksheet, 10th graders solve problems that are based on the theorems associated with perpendicular and angle bisectors of a triangle.  An application on the coordinate plane is included.  The one page worksheet contains...
+
Interactive
Curated OER

Tangents

For Students 10th - 12th
For this tangents worksheet, students use tangent ratios to find the length of the sides of right triangles. This one-page worksheet contains 10 multi-step problems.  Answers are provided.
+
Assessment
Inside Mathematics

Rhombuses

For Teachers 9th - 12th Standards
Just what does it take to show two rhombuses are similar? The assessment task asks pupils to develop an argument to show that given quadrilaterals are rhombuses. Class members also use their knowledge of similar triangles to show two...
+
Lesson Plan
EngageNY

From Circle-ometry to Trigonometry

For Students 10th - 12th Standards
Can you use triangles to create a circle? Learners develop the unit circle using right triangle trigonometry. They then use the unit circle to evaluate common sine and cosine values.
+
Worksheet
Curated OER

Geometry Practice: G.G. 28 #2: Triangle Congruence

For Students 10th - 12th
In this triangle congruence worksheet, students use SSS, ASA, AAS and HL to determine the congruence of triangles.  They identify the theorem that proves congruence.  This three-page worksheet contains 4 multi-step problems.  Answers are...
+
Worksheet
Curated OER

Similar Right Triangles-Introductions to Trigonometry

For Students 9th - 10th
In this geometry worksheet, students examine similar right triangles as the basis for the foundation of trigonometry. Students define the basic trigonometric functions and use a calculator to find the trigonometric value of an angle. The...
+
Worksheet
Curated OER

Classifying Triangles

For Students 10th
In this classifying triangles worksheet, 10th graders solve 9 various problems that classify triangles into categories. First, they refer to the figure shown of an isosceles triangle with two line parallel. Then, students name the sides,...
+
Lesson Plan
Curated OER

Right Triangle Geometry

For Teachers 9th - 11th
Students study the basic principles of right triangle geometry needed to solve for unknown values of a right triangle. They apply and master the principles of right triangle geometry by solving problems.
+
Organizer
Curated OER

Types of Triangles

For Students 9th - 10th
As a reference sheet for types of triangles, this worksheet would be good for students to keep in their binder or to take notes about; however, it would need to accompany an existing lesson as there is no activity beyond basic...
+
Handout
El Paso Community College

Geometry Definitions

For Students 7th - 9th Standards
Geometry is full of shapes, figures, and corresponding things here and there. The guide shares all of the key pieces of geometric information in a nicely color-coded and labeled sheet. 
+
Interactive
CK-12 Foundation

Unit Circle: Medieval Castle Defense

For Students 10th - 12th Standards
Who needs a plan — let trigonometry protect you! Pupils determine the angle of an approaching enemy to a village wall. The scholars determine the exact value of trigonometric functions for the angle. Class members use trigonometry to...
+
Unit Plan
PBS

Accessible Shapes

For Teachers 6th - 8th Standards
All the 2-D and 3-D measurement work you need is in one location. Divided into three sections, the geometry lesson plans consist of visualization of three dimensions, classifying geometric figures, and finding surface area and volume....
+
Worksheet
Curated OER

Find The Missing Angle of Triangles

For Students 5th - 6th
In this triangle worksheet, students find the missing angle in a set of 4 triangles. Answers are included on page 2. A reference web site is given for additional activities.
+
Worksheet
Curated OER

Identify Angles: Obtuse, Right, Straight and Acute

For Students 5th - 6th
In this triangle worksheet, students identify angles as either obtuse, right, straight or acute. A reference web site is given for additional activities.
+
Worksheet
Curated OER

Triangle Review

For Students 5th - 6th
In this triangle review instructional activity, learners define what type of triangle is being described, then draw a picture of it. A reference web site is given for additional activities.
+
Lesson Plan
Curated OER

Congruent Triangles

For Teachers 10th
Tenth graders explore congruent triangles.  In this geometry lesson, 10th graders investigate the conditions necessary to prove two triangles are congruent by SSS, ASA, AAS, or SAS. 
+
Worksheet
Curated OER

Triangle Inequalities

For Students 9th - 10th
In this geometry worksheet, students use the inequality theorem to figure out if three segments will make a triangle. They are given the measures of two segments and must figure out the third segment on their own. There are 20 questions.
+
Interactive
Curated OER

Trigonometry Applications

For Students 10th
In this geometry worksheet, 10th graders solve application word problems involving the use or right triangle trigonometry, including angle of elevation or depression. The one page interactive worksheet contains five questions. Hints,...