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)
(x-400)/x = 0.2 // - 0.2
(x-400)/x-0.2 = 0
(x-400)/x+(-0.2*x)/x = 0
x-0.2*x-400 = 0
0.8*x-400 = 0
(0.8*x-400)/x = 0
(0.8*x-400)/x = 0 // * x
0.8*x-400 = 0
0.8*x-400 = 0 // + 400
0.8*x = 400 // : 0.8
x = 400/0.8
x = 500
x = 500
| -7+7-5= | | -19+18= | | 54x-198=45x | | https://vle.mathswatch.com/images/questions/question412.png | | x-400/400=0.2 | | -(2x+3)=x-5 | | 9m-26=28 | | 9m+24=6+m | | -9+8-1+4+3-2-9= | | 4+x=3+5x-1 | | 3-2-9= | | (1+xy)xdy+(1-yx)ydx=0 | | 2sin(3x-4)=1 | | 2sin(3x-4)=sqrt(3) | | 1-13-9-3= | | -9+8-7+6-5+4-3= | | 18x-18=14x+26 | | 20p+16p+p-5q-5p= | | 4+5p=2p-6 | | -3+4+5-6-9+10-2= | | 9m-24=6+m | | 240=a*200+b | | 7-2x+15=35+1x | | 5(t-30)=25 | | 21a+14= | | 4(5*5)-(4*7)= | | 16+(3y-2)-14y= | | x+3y=43 | | 3(2x-2)=2x+34 | | Y=2x^2-6x+4.5 | | 5(4x-4)-9=x-48 | | 8x+9=72x-9 |