Curated OER
Indirect Measurement with Similar Triangles
Young scholars use similar triangles to find missing heights. In this using similar triangles to find missing heights lesson, students use proportions to find the heights of missing side lengths. Young scholars find the height of trees...
Curated OER
Measurement of Objects Using Similar Triangles in The Plane
Students use similar triangles and a sight tool to find the height and distance between large objects. In this similar triangles lesson plan, students use a constructed sight tool to measure the distance and height of an object using an...
EngageNY
Modeling Using Similarity
How do you find the lengths of items that cannot be directly measured? The 13th installment in a series of 16 has pupils use the similarity content learned in an earlier resource to solve real-world problems. Class members determine...
Utah Education Network (UEN)
Finding Missing Lengths of Similar Triangles
Middle and high schoolers explore the properties of similar triangles. In this geometry lesson, pupils play a similarity basketball game, sketch similar triangles, and find the missing measures of similar figures. They find the height of...
Curated OER
Similar Triangles
Ninth graders find the height of every day objects using techniques learned through postulates that allow triangles in a problem to be similar. They calculate the length of a missing side and solve proportions.
Curated OER
Similar Triangles - Applied Problems
Students differentiate between similar and congruent triangles. In this geometry lesson, students identify the angles of triangles using the similarity theorem. They apply concepts of triangles to the real world.
EngageNY
Between-Figure and Within-Figure Ratios
Tie the unit together and see concepts click in your young mathematicians' minds. Scholars apply the properties of similar triangles to find heights of objects. They concentrate on the proportions built with known measures and solve to...
Curated OER
Tennis Triangle
Students calculate the height of a tree or flagpole. They measure the shadow of the tree or flagpole and the length of a shadow of a meterstick. Using similar triangles, calculate the heigh. Devise two additional ways in which to measure...
Illustrative Mathematics
Equal Area Triangles on the Same Base II
A deceptively simple question setup leads to a number of attack methods and a surprisingly sophisticated solution set in this open-ended problem. Young geometers of different strengths can go about defining the solutions graphically,...
Curated OER
II Similar
Learners, through lecture and guided practice, discover the properties of similar triangles. They use given measurements of one triangle to find a missing measurement of a similar triangle. They apply this knowledge in real-life...
Project Maths
Introduction to Trigonometry
The topic of trigonometric ratios is often covered with loads of rote memorization baked into the activity. This activity set, however, leans more on using similar triangles and discovery learning to help young geometers develop a deeper...
Curated OER
Measuring Heights With Triangles
Students identify the different properties of triangles. In this geometry lesson, students differentiate between congruent and similar triangles. They use mathematical reasoning to solve word problems.
Willow Tree
Area of Common Geometric Figures
Scholars can use area formulas, but can they apply what they know about area? The lesson challenges learners to think logically while practicing finding area of shapes such as rectangles, circles, parallelograms, triangles, and other...
EngageNY
Truncated Cones
Learners examine objects and find their volumes using geometric formulas in the 21st installment of this 25-part module. Objects take the shape of truncated cones and pyramids, and individuals apply concepts of similar triangles to find...
Curated OER
How Tall Is That Flag Pole?
Students examine various triangles and discuss how similar triangles have sides that are proportional. They utilize an ancient Egyptian method to determine the height of a flagpole.
Curated OER
Altitude Locator
Students use protractors, strings, and straws to construct a device used to determine the height of tall objects. In this applied geometry lesson, students use common objects to construct a tangent height guide. They use principles of...
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
General Pyramids and Cones and Their Cross-Sections
Are pyramids and cones similar in definition to prisms and cylinders? By examining the definitions, pupils determine that pyramids and cones are subsets of general cones. Working in groups, they continue to investigate the relationships...
Curated OER
Introducing Trig
Fifth graders explore the importance of triangles in the real world. They find the unknown side of a right triangle using a scale drawing. Students use Pythagoras' Theorem and other appropriate ratios.
Curated OER
How to weigh a tree
Students pick a tree they see everyday. They measure the tree's circumference and estimate its height using similar triangles. Students are introduced to Computational Science. They use computers and calculators to compute values...
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
Definition and Properties of Volume
Lead a discussion on the similarities between the properties of area and the properties of volume. Using upper and lower approximations, pupils arrive at the formula for the volume of a general cylinder.
Curated OER
Simson Line
Stuednts identify triangles for the Simson Line. In this geometry activity, students solve triangular problems using the properties of triangles.They differentiate between the height, congruency and similarity.
Curated OER
What Goes Around
Fourth graders investigate the relationships between the area and perimeters of squares and rectangles. They calculate the perimeter of rectangles and squares using a formula. Students investigate the relationship between the perimeter...