Given:
The coordinates of the pre-image DEFG are D(2,0) E(2,2), F(5,2), G(5,1).
To find:
The coordinates of the image of D'E'F'G' after a rotation of 90º counterclockwise.
Solution:
If a figure is rotated 90º counterclockwise, then
[tex](x,y)\to (-y,x)[/tex]
Using this rule, we get
[tex]D(2,0)\to D'(0,2)[/tex]
[tex]E(2,2)\to E'(-2,2)[/tex]
[tex]F(5,2)\to F'(-2,5)[/tex]
[tex]G(5,1)\to G'(-1,5)[/tex]
Therefore, the coordinates of the image of D'E'F'G' after a rotation of 90º counterclockwise are D'(0,2), E'(-2,2), F'(-2,5) and G'(-1,5).
