Similar shapes are all about the scale. Given seven problems, pupils use scale factors to determine measurements within similar shapes. While solving the problem, scholars also determine whether two figures are similar and use area and...

Challenge your classes while developing their problem-solving skills. A square is divided neatly into four equal triangles by its diagonals until one diagonal is moved from a vertex to the midpoint of one side. Now, scholars must devise...

What do similar triangles have to do with linear equations? Building on prior knowledge of similar triangles, learners discover that the slope of the sides of similar triangles is the same. They make their discoveries while graphing...

Congruent sides + congruent angles = congruent triangles. Scholars first create several triangles that satisfy given conditions using straws. They investigate the triangles to see which are congruent, and then they define what it means...

Strike a chord length. The section of a larger playlist on geometry introduces the relationship relating lengths of intersecting chords. Using the relationship, the video shows how to find lengths of segments of the chords.

Judging by the sides, things appear similar. A portion of a larger playlist on geometry introduces the Side-Side-Side Similarity Theorem. The video shows how to use the lengths of sides to determine whether triangles are similar.

As if geometry weren't puzzling enough! Give your classes a challenge to solve and watch as they discuss and develop ideas. Part of a larger playlist that explores physics concepts, the video lesson offers a presentation of the puzzle...

Can you hear me from there? Pupils determine the place to build a cell tower on a hill. The class uses constraints and creates a scale drawing on a coordinate system to calculate the exact location of the base of the cell tower.

Bank on geometry to line up the shot. The resource asks the class to determine the location to bank a cue ball in a game of billiards. Using their knowledge, class members determine where to hit the bumper to make a shot and discuss...

Look at proportionality from a parallel perspective. A section of an expansive geometry playlist introduces the Triangle Proportionality Theorem. Using the theorem, the video shows how to determine missing measurements in triangles.

When the tape measure will not reach, use similarity. An installment of a large playlist on geometry introduces the method of indirect measurement. Using a story of finding the distance to the sun, the video shows how to use similar...

Two sets of congruent angles leads to three. Using diagrams of two triangles, the presentation intuitively shows that if two sets of angles are congruent, the third set is too. The portion of a geometry playlist uses that information to...

Create similar triangles with a little altitude. A section of an extensive playlist on basic geometry discusses how an altitude of a right triangle creates similar triangles. Using the theorem, the presentation finds unknown side...

When given two sides and an angle, make similar triangles. The video describes the SAS Similarity Theorem. Using the theorem, the segment of a larger geometry playlist determines whether two triangles are similar.

Given two congruent triangles, the resource provides the definition of congruent triangles and marks the corresponding parts. The portion of a basic geometry playlist shows the triangles are congruent by moving one on top of the other...

Are two angles enough? Given two triangles, the class determines through the definition of similarity and transformations whether the two triangles are similar. Provided with pairs of triangles and measurements, small groups find out...

Are all the measurements scalable? Pupils work in groups or alone to determine whether figures are similar and find any missing side lengths. Then, they calculate the perimeters and areas of the figures. Finally, using the measurements,...

How do you measure a distance where the measurement tool will not reach? Pupils use the concept of similar triangles to perform indirect measurements. The lesson asks teachers to demonstrate the method and lead the class through a set of...

Discover how to divide the sides in half to create fourths. Using construction tools, learners find the midpoints of the three sides of two triangles. First, they create four triangles by drawing in the line segments connecting the...

Similar or not? Scholars use a given diagram of two triangles on a coordinate plane to determine if the triangles are similar. They must use similarity transformations to prove their answers.

Stretch the class' knowledge of dilations. With the aid of the rubber band stretcher tool, learners perform dilations. They dilate the triangle by a whole number scale and a fractional scale from two centers of dilation.

There is more than one way to prove the Pythagorean Theorem. Euclid and Einstein found the same way to prove the Pythagorean Theorem. The video introduces several other ways to prove the theorem along with the history of its use.

Gain some altitude with the geometric mean. Pupils discover the relationship between the three triangles formed by drawing the altitude to the hypotenuse in a right triangle. The lesson introduces the geometric mean and provides problems...

Pupils use a parallelogram containing intersecting line segments to identify two similar triangles. They justify the similarity and use it to find a missing length.