y=x^2-81/6x^2-x-2

Solution for y=x^2-81/6x^2-x-2 equation:

x in (-oo:+oo)

y = x^2-((81/6)*x^2)-x-2 // - x^2-((81/6)*x^2)-x-2

(81/6)*x^2-x^2+x+y+2 = 0

25/2*x^2+x+y+2 = 0

DELTA = 1^2-(4*25/2*(y+2))

DELTA = 1-50*(y+2)

1-50*(y+2) = 0

1-50*(y+2) = 0

-50*y-99 = 0

-50*y-99 = 0

-50*y-99 = 0 // + 99

-50*y = 99 // : -50

y = 99/(-50)

y = -99/50

DELTA = 0  <=>  t_1 = -99/50

x = -1/(2*25/2) i y = -99/50

x = -1/25 i y = -99/50

( x = ((1-50*(y+2))^(1/2)-1)/(2*25/2) or x = (-(1-50*(y+2))^(1/2)-1)/(2*25/2) ) i y > -99/50

( x = ((1-50*(y+2))^(1/2)-1)/25 or x = (-((1-50*(y+2))^(1/2)+1))/25 ) i y > -99/50

y+99/50 > 0

y+99/50 > 0 // - 99/50

y > -99/50

x in { -1/25, ((1-50*(y+2))^(1/2)-1)/25, (-((1-50*(y+2))^(1/2)+1))/25 }