I gave the students this warm up to refresh them on Pythagorean theorem and special 90 degree triangles.
We learned about the 45-45-90 and 30-60-90 and how to solve them last week. We wanted the students to look ate these triangles and analyze them and figure out what they need to do to find the missing angles and sides.
Before they started....
There was a poster on the white board for the students to reference that i went over before they started. It stated,
- If two sides are known, then do the Pythagorean theorem and I provided the theorem.
- If one side is known, see if the triangle is a 45-45-90 or a 30-60-90 triangle and then do the equations for those triangles. Then proved a drawing of both triangles at the bottom with the equations for them for the students to reference.
Another item we made sure they remembered was that the inside of a triangle equals 180 degrees.
How it went...
The angles
- Some of the students figured out the angles with out any help.
- A few had to be reminded what the inside of the triangle should equal.
- The last problem, many students need help with because they forgot what an equilateral triangle was and how it worked. I would mostly remind them that it was an equilateral triangle and they were able to figure it out from there. Some I had to walk them through it.
The sides
- Many seemed to be struggling with what to do, so I went back to the poster to emphases the two ways of finding the sides of triangle. Mostly saying that if they know the amount for two sides, the easiest is to use the Pythagorean theorem.
- With that many were able to get them, but would trip on the placement of the Pythagorean theorem. or they would forget about taking the square root of both sides to get the answer.
- The 3 problem was a 45-45-90 problem and I think I had one or two students remember how to solve it. Others, I started them on how to do it and they remembered from there.
The Pros
It was great to see how they could analyze a triangle and figure out all the information. It is important that they can do that without us there to walk them through it.
The Cons
The fact that some of them had to be remined again that the triangle interior angles equal 180 degrees. This is the third time in 2 weeks that we went over this and it was just a review from the past.
How do I know what they learned...
By walking around I was able to see that they were either getting or not. We did go over all three together at the end.