I had a thought about another way to approach that ellipse and circles problem and thought I’d try it on a generalization. Suppose the circle is of arbitrary radius and sitting at an arbitrary point? 635 more words

## Tags » Geometry

#### An elliptical tangent

Another oddball ellipse topic: Let’s suppose you have two unit circles (*r*=1) adjacent, i.e. tangent, to one another, and you want to draw an ellipse that contains them. 835 more words

#### Dividing ellipses

Yeah, I’m still around.

I’ve been thinking about ellipses lately. For Reasons.

Here’s a sort of silly question. Suppose I gave you a circle and asked you to mark four points on it, evenly spaced. 1,275 more words

#### Origami Regular Octagon

We folded a square piece of paper as described in the Illustrative Mathematics task, Origami Regular Octagon. I didn’t want students to know ahead of time that they were creating an octagon, so I changed the wording a bit. 587 more words

#### Always, Sometimes, Never

I debated some Always, Sometimes, Never statements with my Geometry kids today. In groups, they had to choose the word that they thought went in the blank, as well as draw a picture to explain their choice. 423 more words

#### Locating a Warehouse

We changed the Learning Mode to individual. Where would you place a warehouse that needed to be equidistant from all three roads? (From Illustrative Mathematics… 489 more words

#### High and Lows (Mostly Highs!) of the First Two Weeks

I survived my first two weeks as a high school math teacher! So many things have been running through my mind, but right now I’m going to make a list of things that are going well and things that need improvement. 552 more words