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 15 Page 567

A 90^(∘) rotation counterclockwise about the origin will change the coordinates of the vertices such that (a,b)→ (- b,a).

Practice makes perfect

Let's begin by drawing △ LMN.

When a figure is rotated 90^(∘) counterclockwise about the origin, the coordinates of the image's vertices will change in the following way. preimage (a,b)→ image (- b,a)

Using this rule on the vertices of △ LMN, we can find the coordinates of the rotated figure.

Point (a,b) (- b,a)
L (1,6) (- 6,1)
M (- 2,4) (- 4,- 2)
N (3,2) (- 2,3)

Now we can draw △ L'M'N'.

The second transformation is a translation of △ L'N'M' by 3 steps to the left and 2 steps up. (x,y) → (x - 3,y + 2) Let's perform these translations.

Finally, we will remove △ L'M'N' from the diagram.