Question 1064544
Your function of x is also a function of y. 
{{{h(x,y)=32x^2-80x+50-18y^2}}}
{{{h(x,y)=2(16x^2-40x+25)-18(y-0)^2}}}
{{{h(x,y)=2(4x-5)^2-18(y-0)^2}}}