I was given the equation: 2sqrt(2)(x+y)^2=7x+9y

I need to then:

a)Use rotation of axes to show that the following equation represents a parabola

b) Find the XY- and xy- coordinates of the vertex and focus

c) Find the equation of the directrix in XY- and xy-coordinates

Can someone show me how to do this problem so I can do similar problems on my own