Assume 25x2+4y2+150x+8y-171=0 is the equation of the ellipse.
We need to complete the squares for x and y.
25x2+150x+4y2+8y-171=0,
25(x2+6x+9-9)+4(y2+2y+1-1)=171,
25(x+3)2-225+4(y+1)2-4=171,
25(x+3)2+4(y+1)2=171+225+4=400,
(x+3)2/16+(y+1)2/100=1 is the standard form for the ellipse, centre at (-3,-1). Vertical ellipse with vertical radius 10 and horizontal radius 4.