Learners discover a method for determining the slope of a line by creating and comparing similar triangles. They fold coordinate grids to make three similar triangles then measure the sides to compare the relationships between the...

Students 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.  Students find the height of trees...

Looking at numerous examples of triangles, each with different properties, geometers develop their understanding of congruency. They use the notation of a counter-example to disprove certain conjectures and prove geometric theorems and...

High schoolers identify properties of triangles. In this geometry lesson, students differentiate between similar and congruent triangles. They use the umber of sides to help define the angle of the polygon.

In this geometry worksheet, students solve problems using the similarity and congruent theorem. They find the vertices and different parts of polygons using theorems. There are 18 questions.

Students investigate properties of circles. In this geometry lesson plan, students differentiate between similarity and congruence as they observe polygons. They investigate properties of two and three dimensional shape.

How similar do figures have to be to be similar figures? Individuals learn to identify similar figures by verifying that angles are congruent and sides are proportional. Additionally, they match the corresponding parts of similar figures.

Pupils work in pairs to investigate what it takes to prove that two triangles are similar. They work through various shortcuts to find which are enough to show a similarity relationship between the triangles. Small groups work with the...

Looking for a different approach to triangle congruence criteria? Employ transformations to determine congruent triangles. Learners list the transformations required to map one triangle to the next. They learn to identify congruence...

Let your use of the resource be in proportion to its usefulness. Pupils investigate similar triangles by measuring side lengths and considering given angle measures. The results of the investigation help develop generalizations about...

In this similar and congruent polygons worksheet, students learn to solve problems using similar and congruent polygons. Students solve six problems.

Label angles of parallel lines to analyze the angles created by a transversal and two parallel lines. They graph their lines and observe the similarity and difference in the angles.

In this geometry worksheet, students identify the length of the different sides using equations. They solve for the unknown to identify similarity and congruence in angles and sides. There are 22 questions.

After learning that the sum of interior angles for triangles is 108 degrees, take it further to show that the sum of angles in any polygon is the same! Using hexagons, pupils practice finding the measure of the six congruent angles. Make...

Create the ultimate miniature golf course. The 93-page model curriculum unit from the Massachusetts Department of Elementary and Secondary Education contains nine lessons on understanding similarity in terms of both Euclidean geometry...

Seventh graders determine whether two triangles are congruent and provide an explanation to why they are not. They apply concepts of measurement of angles and collect evidence of congruent angles in the world.

In this triangle similarity learning exercise, 10th graders solve and complete 12 different problems that include defining similar and 3 similar statements using only sides and angles. First, they determine if each pair of triangles...

Learners compare and contrast angles and identify them as acute, obtuse, right, or straight angles. They create rays and angles using uncooked spaghetti, read and discuss key vocabulary terms, and complete a variety of geometry worksheets.

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. 

In this similar-congruent worksheet, students determine measures of unknown angles, draw congruent shapes and determine whether shapes are congruent. A reference web site is given for additional activities.

Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...

Without ever using the actual term, this exercise has the learner develop the key properties of the midsegment of a triangle. This task leads the class to discover a proof of similar triangles using the properties of parallel...

Acute angle, line of symmetry, and vertex are a few terms you'll find in a set of 90 flashcards designed to reinforce math vocabulary. Included in the set are two types of cards; a word card printed in bold font, and a...

The class gets to practice being a mathematician in ancient Greece, performing geometric application problems in the way of Eratosthenes. After following the steps of the great mathematicians, they then compare the (surprisingly...