Inside Mathematics
Hopewell Geometry
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...
CK-12 Foundation
Secant, Cosecant, and Cotangent Functions: Hold the Ladder!
Determine the length of a falling ladder. Pupils use an interactive to find the angle a ladder makes with the floor after it falls to answer questions. The scholars use the triangle formed in the interactive to determine values of...
EngageNY
End-of-Module Assessment Task - Geometry (module 2)
Increase the level of assessment rigor with the test of performance tasks. Topics include similar triangles, trigonometric ratios, Law of Sines, Law of Cosines, and trigonometric problem solving.
Mathematics Assessment Project
Solving Problems with Circles and Triangles
After completing a task involving examining the ratio of areas of triangles and circles in a given figure, scholars examine sample responses to identify other strategies they could use to solve the problem.
Curated OER
Trigonometry Ratios
Learners identify the different angles and sides of a triangle. In this geometry lesson, students identify the six trigonometric ratios. They graph the graph of each trig function and analyze it.
Concord Consortium
Measuring the Unit Circle
Here's the right task to investigate right triangles in the unit circle. A short performance task has learners determine the product of two side lengths in a unit circle. They must apply similarity concepts and trigonometric ratios to...
CK-12 Foundation
Angles of Elevation and Depression: Fly-By Calibration
Determine the distance between two trees from afar. Pupils use an interactive resource to create two right triangles using trees and a plane. They determine the horizontal legs of each triangle to find the distance between the two trees.
CK-12 Foundation
Sine, Cosine, and Tangent Functions: Lighthouse
How far is that boat from the lighthouse? Scholars create diagrams to represent a scenario given the angle of depreciation from a lighthouse to a boat. Learners apply the basic trigonometric functions to find various distances stemming...
Curated OER
Trig River
Students calcute distances using trigonometry and angle measurements. They estimate the width of the Trig River, measure it and compare their results with their classmates. They collaborate with a group to research and find the results.
Curated OER
Similar Right Triangles-Introductions to Trigonometry
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...
EngageNY
Law of Cosines
Build upon the Pythagorean Theorem with the Law of Cosines. The 10th part of a 16-part series introduces the Law of Cosines. Class members use the the geometric representation of the Pythagorean Theorem to develop a proof of the Law of...
Curated OER
Amazing Consistent Ratios
Students derive the six trigonometric identities. In this trigonometry lesson, students find the ratios of sine, cosine and tangent using the right triangle. They use properties of the Pythagorean Theorem to find the trig identities.
Curated OER
ndirect Measurement Technique: Using Trigonometric Ratios
Ninth graders find the height of an object that would be difficult or impossible to measure directly. They construct and use a Clinometer to measure the angle of elevation (or depression). Students create a sketch of the measurement...
Curated OER
Investigating the Idea of Sin
Fifth graders use sin to solve problems involving right-angled triangles, Solve equations of the form sin(++) = a, for a between -180++ and 360++. They State and graph the value of sin(++) in special cases. They describe some of the ways...
Curated OER
Math: Investigating Triangles
Tenth graders identify the trigonometric ratios for right angled triangles. Through independent investigation, they discover the constancy between the ratios of any two sides of similar triangles. In an alternative method, 10th graders...
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.
Radford University
REALLY Tall!
Conduct indirect measurements three ways. Working in groups, pupils come up with different ways to measure three tall objects indirectly. The teacher provides measurement information requested by the teams, and learners then calculate...
Curated OER
Investigating the Idea of Cos
Fifth graders use cos to solve problems involving right-angled triangles. They solve equations of the form cos(++) = a, for a between -180 and 360 degrees. They state the value of cos(++) in special cases and graph y = cos(++).
Mathematics Assessment Project
Solving Quadratic Equations
Scholars first complete an individual assignment using a quadratic equation to model the movement of a bus around a corner. Learners then discuss their solutions with classmates and analyze the provided sample responses.
Curated OER
The Diagonal Of A Box
Students solve problems using the pythagorean theorem. They use critical thinking skills in order to use a systematic process to solve the problem. Upon solving each problem the uniqueness of the lesson is asking students to give an...
Curated OER
Dizzy Heights
Fifth graders explore ways to measure the height of an inaccessible object. They measure lengths using a tape measure or ruler. Students measure angles using a protractor and estimate heights.
EngageNY
Complex Numbers and Transformations
Your learners combine their knowledge of real and imaginary numbers and matrices in an activity containing thirty lessons, two assessments (mid-module and end module), and their corresponding rubrics. Centered on complex numbers and...
Curated OER
CORNER CABINET
Ninth and tenth graders calculate the length, width, height, perimeter, area, volume, surface area, angle measures or sums of angle measures of common geometric figures. They solve problems involving scale drawings, models, maps or...
EngageNY
Cyclic Quadrilaterals
What does it mean for a quadrilateral to be cyclic? Mathematicians first learn what it means for a quadrilateral to be cyclic. They then investigate angle measures and area in such a quadrilateral.