This is a reflection over the x-axis.
To remember the difference between reflectinon over the x-axis and reflectino over the y-axis, memorize this.
If you reflect over the x-axis, the x value of the reflected point stays the same. (only the y is multiplied by -1)
If you reflect over the y-axis, the y value of the reflected point stays the same. (only the x is multiplied by -1)
Roation about the origin involves multiplying both x and y by -1. (x and y change)