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^2-(8*x)+15 = 0
x^2-(8*x)+15 = 0
x^2-(8*x)+15 = 0
x^2-8*x+15 = 0
x^2-8*x+15 = 0
DELTA = (-8)^2-(1*4*15)
DELTA = 4
DELTA > 0
x = (4^(1/2)+8)/(1*2) or x = (8-4^(1/2))/(1*2)
x = 5 or x = 3
x in (-oo:3) U (3:5) U (5:+oo)
(x^2-x-12)/(x^2-(8*x)+15) = 0
(x^2-x-12)/(x^2-8*x+15) = 0
x^2-x-12 = 0
x^2-x-12 = 0
DELTA = (-1)^2-(-12*1*4)
DELTA = 49
DELTA > 0
x = (49^(1/2)+1)/(1*2) or x = (1-49^(1/2))/(1*2)
x = 4 or x = -3
(x+3)*(x-4) = 0
x^2-8*x+15 = 0
x^2-8*x+15 = 0
DELTA = (-8)^2-(1*4*15)
DELTA = 4
DELTA > 0
x = (4^(1/2)+8)/(1*2) or x = (8-4^(1/2))/(1*2)
x = 5 or x = 3
(x-3)*(x-5) = 0
((x+3)*(x-4))/((x-3)*(x-5)) = 0
( x+3 )
x+3 = 0 // - 3
x = -3
( x-4 )
x-4 = 0 // + 4
x = 4
x in { -3, 4 }
| 32x=81 | | 40=-3x^2+12x+135 | | 15b^2-17bc-4c^2= | | y=1/6x-2 | | y=-8*3+15 | | (x-2)/(x+1) | | 6y-1+2y=7 | | 1+9y=8y | | (x-3)/(x-2) | | -60z^5+16z^4+12z^3= | | 8x+y=15 | | 2.4(m-3)+2=26 | | 15-4*2+2= | | x+9=x-3 | | -1/20+9/10= | | -3(5s-6)-18=-3(7s+7)-3 | | 12x+7(1-x)=4(x+1) | | 73/4-36/7 | | -60z^5+16z+12z^3= | | y-8=-(6/7)x | | 4-m/5 | | y-8=(-6/7x) | | -6x+4-2x=4-10x+4 | | 2*y+2+y=1 | | 6/7=54/2 | | (33b-8)-8(4b+4)=-2 | | -2y+3=-7 | | x^3-4x^2+16x=0 | | 40m-10m=30 | | 9m+7-3b=2 | | 0.003x^2+35x-42=0 | | s^2-3sx-70x^2=0 |