Question

what are the coordinates of the vertices of the image of rectangle wxyz after the transformation (r_{0,90^{circ}}(x,y))? w(-4, -1) x y z(-4, 2)

Explanation:

Step1: Recall rotation rule

The rule for a 90 - degree counter - clockwise rotation about the origin $R_{0,90^{\circ}}(x,y)=(-y,x)$.

Step2: Find coordinates of X

Assume the coordinates of $X$ are $(- 1,2)$. Using the rotation rule $R_{0,90^{\circ}}(-1,2)=(-2, - 1)$.

Step3: Find coordinates of Y

Assume the coordinates of $Y$ are $(1,2)$. Using the rotation rule $R_{0,90^{\circ}}(1,2)=(-2,1)$.

Answer:

$X'(-2, - 1)$
$Y'(-2,1)$