Question 752759
Put this conic section into standard form. What is the a^2 value? 
25x^2 + 16y^2 + 150x = 160y - 225
complete the square
25x^2+150x+16y^2-160y = -225
25(x^2+6x+9)+16(y^2-10y+25) = -225+225+400
{{{(x+3)^2/16+(y-5)^2/25=1}}}
This is an equation of an ellipse with vertical transverse axis.
Its standard form: {{{(x-h)^2/b^2+(y-k)^2/a^2=1}}} , (h,k)=(x,y) coordinates of center
a^2=25