Harvard 9/24/12
Journal: Things I've Learned
What have you learned this week about congruence and transformations? What properties (size, shape, orientation) of an image, if any, change when you perform each of the transformations studied this week? How does the orientation (location) change for each type of transformation? Where are some places in your world that you see transformations?This week, I've learned about congruence, transformation, properties of an image, location of a transformation, and places in the world with transformations.
Congruence is when a figure have the same size and shape. If two polygons are congruent, all of their angles have corresponding sides and angles. I learned that a transformation is a change in a figure's position or size. The three types of transformation are rotation, translation, and reflection. A ration is when you turn a polygon. For example, when you rotate a figure180 degrees, your answer will look like this: (x,y)= (-x,-y), when you rotate a figure 90 degrees clockwise, your answer might look like this: (x,y) = (y,-x), and a 90 degrees counterclockwise rotation gives you, (x,y)= (-y,x). Translation is when you slide a figure along a line without turning it. For instant, when you "Move right a unit", your answer will look like this: (x,y)= (x+a,y). If you "Move left a units", you'll get (x,y)= (x-a,y). When you "move up b units, your result will appear like this: (x,y)= (x,y-b). Reflection is when you flip a figure across a line to create a mirror. When you reflect a figure across the y-axis, you will get (x,y)= (-x,y) and across the x-axis, you will get (x,y)= (x,-y). An example of rotation is when the earth spins/rotate around the sun or when I go to the park and see Ferris Wheels. Reflection is when I look at my self in the mirror. Also a translation would be me walking down the stairs. Therefore, these are the things I've learned this week in class.
