If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( x )
x = 0
x = 0
x = 0
x in (-oo:0) U (0:+oo)
(4/5)*x+1/x-15-3 = 0
4/5*x^1+1*x^-1-18*x^0 = 0
(4/5*x^2-18*x^1+1*x^0)/(x^1) = 0 // * x^2
x^1*(4/5*x^2-18*x^1+1*x^0) = 0
x^1
(4/5)*x^2-18*x+1 = 0
(4/5)*x^2-18*x+1 = 0
DELTA = (-18)^2-(1*4*(4/5))
DELTA = 1604/5
DELTA > 0
x = ((1604/5)^(1/2)+18)/(2*(4/5)) or x = (18-(1604/5)^(1/2))/(2*(4/5))
x = 5/8*((1604/5)^(1/2)+18) or x = 5/8*(18-(1604/5)^(1/2))
x in { 5/8*(18-(1604/5)^(1/2)), 5/8*((1604/5)^(1/2)+18)}
x in { 5/8*(18-(1604/5)^(1/2)), 5/8*((1604/5)^(1/2)+18) }
| 1/z-3+4/5x-15 | | 18-3n=2 | | 2x^3+0x^2-2x=0 | | -28.5=-9(2v-8) | | x^2-11x-50=0 | | x(-4x-13)=-1 | | 2x+44=6+12 | | -7(4h+5)=-17.5 | | 5x+30=55 | | w^2+6w+5=0 | | 22.5-6d=3.5(4.4d+4) | | 7(2x+2)=4x | | 26.5=-8f+9.5f | | 6(1.5x+2.5)=24 | | 5-(2+7x)=9x-4 | | 7.5z-8z=29.5 | | 5.94x=11.88 | | 17/12=p/12 | | 9x+7+2x+1+3x+4= | | -600=-20a | | -29+5=4x+5-3x | | 7y=-0.21 | | v-29=-4 | | 3y^2+22y-16= | | -27=r/25 | | 15x+7y=136 | | X/3-14=x/3 | | n-(-3)=-1 | | -9b+3.5+5.5=29.5 | | -15=-4+n | | -64=8x | | 3x-x=7-15 |