Given,
R be a rectangle given by the lines x=0,x=2, y=0 and y=5
And point A(α,0) and B(0,β),α∈[0,2] and β∈[0,5],
Now plotting the diagram we get,

Now given that line segment AB divides the ratio of area in 4:1, we get
21αβ10−21αβ=14
⇒20−αβ=4αβ
⇒αβ=4......(1)
Now using midpoint formula we get,
h=\frac{\alpha }{2}&\beta =\frac{k}{2}
Now using equation (1) we get,
⇒4hk=4
⇒xy=1 which is a equation of rectangular hyperbola.