Pearson Geometry Common Core, 2011
PG
Pearson Geometry Common Core, 2011 View details
3. Rotations
Continue to next subchapter

Exercise 18 Page 565

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

Practice makes perfect

Let's start by looking at the given polygon.

When a figure is rotated 180^(∘) counterclockwise about the origin, the coordinates of the image's vertices will change in the following way.

(a,b)→ (- a,- b) Using this rule and the vertices of the polygon, we can find the x- and y-coordinates of the image's vertices.

(a,b) (- a,- b)
J(3,2) J'(- 3,- 2)
F(0,3) F'(0,- 3)
G(- 4,1) G'(4,- 1)
H(1,- 4) H'(- 1,4)

Knowing the vertices of F'G'H'J', we can draw the image.