EngageNY
Using Trigonometry to Find Side Lengths of an Acute Triangle
Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems.
Curated OER
Applications of Triangles
Students apply the properties of a right triangle. In this triangle lesson, students describe and compare radians to degrees. They solve problems using the properties and ratios of a right triangle.
Curated OER
Solve Right Triangle
In this trigonometric applications worksheet, students solve for the missing side of a right triangle using a trigonometric ratio. There are 46 questions, 10 of which are word problems.
Curated OER
Right Triangles and The Unit Circle
Students solve right triangles using trigonometry. In this geometry lesson, students use the unit circle to identify different trig values. They identify the six trigonometric identities.
Curated OER
Measuring Angles
Middle schoolers explore angle measure as they estimate angle measure and measure and draw angles of less than 360 degrees. The lesson emphasizes the use of estimation when measuring angles.
Curated OER
Perpendicular and Angle Bisectors
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...
Curated OER
Angles in Standard Positions
Students identify positive and negative angles using the Unit Circle. In this pre-calculus lesson, students identify the different angles on a unit circle using the coordinate plane and the four different quadrants as a guide. They...
Curated OER
Measure the Angle
Students measure angles. In this angle lesson, students draw angles. They use a protractor to measure angles and identify the angle as straight, right, acute, or obtuse.
Curated OER
Eleven Angle Addition Postulate and Adjacent Angle Problems
In this angles worksheet, learners use the angle addition postulate, the idea of adjacent angles and the diagrams shown to answer eleven questions
Curated OER
Gougu Rule or Pythagoras' Theorem
Fifth graders explore Pythagoras' Theorem. They examine the pattern linking the length of the hypotenuse of a right angled triangle and the length of the other two sides. Students find an unknown side in right angled triangles.
Curated OER
Discover the Pythagorean Theorem
Students explore the Pythagoras theorem. In this geometry lesson, students make right triangles and identify the parts of the triangle. Students complete measurements of the sides of the triangle.
Curated OER
Practice Problems
In this geometry worksheet, students practice finding the measure of 4 different angles. Students work independently as they refine their ability to correctly calculate the measure of an angle.
EngageNY
Special Triangles and the Unit Circle
Calculate exact trigonometric values using the angles of special right triangles. Beginning with a review of the unit circle and trigonometric functions, class members use their knowledge of special right triangles to find the value of...
Shodor Education Foundation
Squaring the Triangle
Teach budding mathematicians how to square a triangle with an interactive that shows a graphical proof of the Pythagorean Theorem. Pupils alter the lengths of the legs using sliders. Using the inputted lengths, the applet displays the...
Curated OER
Right Triangle Geometry
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.
Curated OER
Skills and Application
For this geometry worksheet, students identify the different properties of parallel lines cut by a transversal. They identify the different angles created by such lines. There are 16 questions.
Curated OER
Exterior and Interior Angles of Triangles
Tenth graders explore the exterior and interior angles of triangles. They use a theorem in order to prove a theorem about all polygons. Students use the theorem and its applications to find the angles of different types of triangles.
Curated OER
Lines, Rays, and Angles
Third graders read "Pigs on the Ball" by Amy Axelrod and discuss the geometry concepts presented in the book. They use Twizzler sticks and pipe cleaners to represent lines, rays and angles.
Curated OER
Pythagorean Theorem and Special Right Triangles
Students review the Pythagorean Theorem and apply it to word problems involving special right triangles.
Curated OER
From Different Angles
Young scholars participate in Socratic seminar discussing a person's right to refuse to say the Pledge of Allegiance.
Curated OER
A Special Relationship
Young scholars discover the relationships of the lengths of the sides of right triangles and right triangles using a series of drawings on dot paper. They investigate and solve problems of standard (customary and metric units) and...
Illustrative Mathematics
Tangent to a Circle From a Point
Learners see application of construction techniques in a short but sophisticated problem. Combining the properties of inscribed triangles with tangent lines and radii makes a nice bridge between units, a way of using information about...
Flipped Math
Inverse Trig Ratios
Put trigonometric ratios into inverse. Scholars learn how to find an unknown angle in a right triangle by using inverse trigonometric ratios. The pupils understand how the inverses undo a trigonometric ratio to provide the angle measure....
CK-12 Foundation
Basic Inverse Trigonometric Functions: Ladder
Lean a ladder against the wall to create an angle. Class members use an interactive application to determine the angle a ladder makes with the ground. Individuals respond to five questions using inverse trigonometric functions.