Reflection -- Roman Selfie

This ancient Roman General is trying to take a full-length selfie in a bathroom mirror. Line Segment CD represents the mirror. Imagine that point E is the camera on his phone. Assume that the whole length of the mirror will be in the frame of any picture he takes.

1. If he stands right where he is, and holds the phone right where it is (-1.98, 3.32), will his picture contain everything from his feet to the top of his head? Explain, and draw or print out a picture of what you did to find out. (Hint: mirrors [i]reflect[/i]. Geogebra has a tool to reflect, too.) 2. Where should he hold the phone to be sure the picture contains his full length? Move point E around to find a spot that will work. What are its coordinates? How did you find this spot/How do you know it will work?

Reflection -- Roman Selfie II

This ancient Roman General is trying to take a full-length selfie in a bathroom mirror. Line Segment CD represents the mirror. Imagine that point E is the camera on his phone. Assume that the whole length of the mirror will be in the frame of any picture he takes.

3. The General really likes the perspective he gets from holding the phone right where it started, at point E. What is the size of the smallest mirror he could use for his full-length selfie? How high should he hang it? (Hint: you can move points C and D up and down.) 4. Describe how you figured it out. You may want to draw or print from the webpage to illustrate your explanation.

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