Big Ideas Math Integrated I, 2016
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Big Ideas Math Integrated I, 2016 View details
3. Rotations
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Exercise 12 Page 566

A 180^(∘) rotation counterclockwise about the origin will change the coordinates of the endpoints such that (a,b)→ (- a,- b).

Practice makes perfect

Let's begin by drawing the segment XY.

When a segment is rotated 180^(∘) counterclockwise about the origin, the coordinates of the image's endpoints will change in the following way. (a,b)→ (- a,- b)

Using this rule on the endpoints of XY, we can find the endpoints of X'Y',

Point (a,b) (- a,- b)
X (- 3,1) (3,- 1)
Y (4,- 5) (- 4,5)

Now we can graph X'Y'

Next, we have to translate X'Y' by going 1 step to the left and 1 step up. (x,y) → (x - 1,y + 1). Let's do this translation.

Finally, we will remove the unnecessary parts of the graph.