One of my classes is at an impasse. They all agree that having proportional sides does not guarantee similarity in a quadrilateral (yay for the students who thought to grab a rhombus and a square from the tub of shapes to prove their point!). Yet we’re stuck on triangles. Half of the students are convinced of side-side-side similarity in triangles, the other half are not. They have been unable to get anyone to change their minds.
I believe they are waiting for me to tell them who is correct.
So, I’m going to try this.
- Measure each side and record.
- Determine if the sides are proportional (they are).
- Determine the scale factor (left as an exercise to the reader).
- Then carefully cut out each segment (kinda worried about this part).
- Next create a triangle out of each set (one triangle will use the letter only sides, one the primed letters).
- Measure the angles. (thinking they may need to tape the triangle together)
- Determine if SSS guarantees similarity in triangles.
I tried it. It seemed doable.
We’ll see how it goes. Any suggestions, advice, insights, criticism is/are of course welcome.
(There are two more sets in the .pdf -bonus, one set is special.)