EngageNY
Similarity and the Angle Bisector Theorem
Identifying and verifying reproducible patterns in mathematics is an essential skill. Mathematicians identify the relationship of sides when an angle is bisected in a triangle. Once the pupils determine the relationship, they prove it to...
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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.
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Similar Triangles
Students differentiate between similar and congruent triangles. In this geometry lesson plan, students identify the missing side and angle of a triangle. They identify the different ratio and proportion of the sides of a triangle.
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Similarity and Congruence
Students explore the concept of similarity and congruence. In this similarity and congruence instructional activity, students cut out strips of paper and form a triangle. Students try to prove that their triangles are congruent using the...
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Baseball Proportion
Eighth graders measure regular baseball bats and souvenir bats in centimeters. They determine how tall a person would be to be in proportion to the souvenir bat, create a poster depicting the person, and explain the proportional...
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Similar Triangles - Applied Problems
Pupils 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.
Illustrative Mathematics
Gotham City Taxis
Taxi! Have your travelers figure out how far they can go in a taxi for $10.00. They must account for the mileage rate and tip in their calculation. They can set up a table or make an equation to solve for the exact mileage they can...
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Investigating Area and Perimeter of Polygons.
Student sinvestigate the area and perimeter of polygons. They differentiate between similar and congruent polygons.. They identify the ratio and proportions of the sides and angles of polygons.
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Triangles & Congruence, Proportions & Similarity, Right Triangle & Trigonometry
Young scholars are introduced to the topic of congruence and proportions in Geometry. Using technology, they construct and validate the properties of various geometric figures and identify whether it is congruent or proportion to the...
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Solve for Scale Factors Using Proportions
Eighth graders solve problems using proportions with scaled drawings. They work with maps and blue-prints discussing scales and plans and examine different polygons and figure out the scale factors or proportions they have been changed by.
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Proportionality Using "Jack & the Beanstalk"
Students apply ideas of proportionality from "Jack and the Beanstalk." They compare objects that are proportional to Jack with those that are in proportion to the Giant. They measure their hands and use those measurements to determine...
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Proportional Segments Between Parallel Lines
High schoolers identify similar triangles. In this proportional segments instructional activity, students identify corresponding sides, set up ratios, and find the length of the missing side of a triangle. They use the...
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Scale Drawing
Students use ratio and proportions to solve problems. In this geometry instructional activity, students apply ratio and proportions to real life scenarios.
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Paper Pool
Students explore ratio and proportion, GCF, and LCM. In this middle school mathematics lesson, students play an interactive Paper Pool game that provides an opportunity to increase their understanding or ratio, proportion, GCF, and...
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Proportional Similarities
Pupils model the geometric relationship with graphing. In this geometry lesson, students differentiate between parallel, perpendicular, similar and congruent shapes. They use properties of polygons to differentiate their shapes correctly.
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7.RP Music Companies, Variation 1
We've got the beat! And your musically-minded mathematicians will tap their toes as they determine which music company would be getting a better deal based on their offers to buy out TunesTown. The topic is extended in an additional task...
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Ratio Relationships
Students solve for the different ratio and proportion of a problem. In this geometry instructional activity, students show their knowledge of how to solve proportional relationships. They convert between percent, decimals and fractions.
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Similarity and Congruence
Students determine that two figures are similar or congruent by
investigating figures that are similar and figures that are congruent. They prove that two figures are similar or congruent by using definitions,
postulates, and theorems.
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Clay Portrait Project
Students discuss facial proportions and mix colors similar to flesh tones. In this art lesson, students draw and paint a portrait and then translate this image into a 3D form using clay.
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Super Size It, Please!
Pupils take photos from a given distance and determine the height of the person using a scale factor. Pupils calculate the ratio of student actual height to student photo height. They take pictures from 3 different distances to see if...
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Maps
Students figure out the mileage from one state to another using a map. In this map lesson, students look at the scale factor and turn it into a fraction. They measure the distance between two cities and use the proportion to find the...
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Can a Geometric Mean be Nice?
In this Geometry instructional (work)sheet, students are instructed on how to find the geometric mean. Students are then shown how the geometric mean is applied to proving similar triangles.
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THE MEAN INDEX CARD
Young scholars cut an index card to create three similar right triangles and explore the congruencies and proportions that exist. They investigate the properties of lines and concepts of congruency, similarity, tangency and symmetry of...
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Proportions in Flight
Sixth graders calculate wingspan and the body length of the birds and understand how they relate to how the bird flies. In this wingspan lesson plan, 6th graders also calculate their own "wing span" with their arms.