y=x^2-4/8-4x

Solution for y=x^2-4/8-4x equation:

x in (-oo:+oo)

y = x^2-(4*x)-(4/8) // - x^2-(4*x)-(4/8)

4*x-x^2+y+4/8 = 0

4*x-x^2+y+1/2 = 0

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

DELTA = 4*(y+1/2)+16

4*(y+1/2)+16 = 0

4*(y+1/2)+16 = 0

4*y+18 = 0

4*y+18 = 0

4*y+18 = 0 // - 18

4*y = -18 // : 4

y = -18/4

y = -9/2

DELTA = 0  <=>  t_1 = -9/2

x = -4/(-1*2) i y = -9/2

x = 2 i y = -9/2

( x = ((4*(y+1/2)+16)^(1/2)-4)/(-1*2) or x = (-(4*(y+1/2)+16)^(1/2)-4)/(-1*2) ) i y > -9/2

( x = ((4*(y+1/2)+16)^(1/2)-4)/(-2) or x = ((4*(y+1/2)+16)^(1/2)+4)/2 ) i y > -9/2

y+9/2 > 0

y+9/2 > 0 // - 9/2

y > -9/2

x in { 2, ((4*(y+1/2)+16)^(1/2)-4)/(-2), ((4*(y+1/2)+16)^(1/2)+4)/2 }