Consider that a rotation of 180° around the origin is given by the following transformation:
(x,y) => (-x,-y)
In the given image you can notice that figure AJG has the following vertices:
A(-4,4)
J(-3,0)
G(0,3)
after the rotation you obtained:
A(-4,4) => A'(4,-4)
J(-3,0) => J'(3,0)
G(0,3) => G'(0,-3)