I have absolutely no idea how to approach this question...

Draw a diagram showing the region enclosed between the parabola y^2=4ax and its latus rectum x=aI drew the diagram...but so far all i have for the area equation is A=2yx (y is doubled because the parabola extends below the axis as well XD)

The, find the dimensions of the rectangle of max area that can be inscribed in this region.

Im having trouble uploading a picture, so ill describe the diagram...its a sideways parabola extending on the right side of the y axis, and the latus rectum cuts the x axis at "a" and the parabola when y= 2a and -2a

Basically, i have no idea what to do...could anyone help?