If it's not what You are looking for type in the equation solver your own equation and let us solve it.
x in (-oo:+oo)
(1/3)*x = -2/21 // + -2/21
(1/3)*x-(-2/21) = 0
(1/3)*x+2/21 = 0
1/3*x+2/21 = 0 // - 2/21
1/3*x = -2/21 // : 1/3
x = -2/21/1/3
x = -2/7
x = -2/7
| 4(n-6)-1=31 | | 1200+x=2(400+x) | | (-8x)(3x^4)= | | 3=ln(x+4) | | 8x-18=45-13x | | 8x-5/8 | | 10=-4n+2n | | 15m^3+6m^4= | | 6.57/.18 | | -4(2m+5)-3m=35 | | X=(sqrt-9)-2 | | X+1+5x=-5 | | 1/2a-1.50 | | 2r-5r=12 | | 1/5xy(5xy)^3 | | 4-b-b=-2 | | 90/100= | | (4x^4-8x)(7x^3)= | | -21=1/2c-11 | | x-6=7+12 | | X+5-6x=-5 | | 12x+25-8x=x-24-5x+9 | | -3p-3p=-18 | | -10(1-9)+6(x-10)= | | 5x+6=74-x | | (5x^-1)/(y^-1) | | -3x^3(x^3+8x)+9x^6= | | 4x+x=-10 | | -3+2b=9 | | 3(x+1)+6=-9 | | 6m+4m=0 | | 5x^-1/y^-1 |