Elizabeth and her family are camping at the lake. Elizabeth and her sister walk to the jetty on the lake. The last sign reads “JETTY” J-E-T-T-Y, but Elizabeth notices that the first T is upside down. Is the first T a translation, reflection, or rotation of the second T?
A translation is moving without rotating or resizing. We know that the T is at least upside down. And that means it can’t be a translation. In a reflection, every point is the same distance from a central line. If the T was reflected across the central line, it would look like this.
But something else is happening here. The first T is a rotation of the second T. If we spin the second T around the point A, we’ll get the first T. In a rotation, the distance from the centre to any point stays the same. We’re spinning the second T around the point A. Point A would be our centre point. That gives a rotation.