If it's not what You are looking for type in the equation solver your own equation and let us solve it.
b in (-oo:+oo)
4/13 = ((6*b)/2)*b+(2*b)/13 // - ((6*b)/2)*b+(2*b)/13
4/13-(((6*b)/2)*b)-((2*b)/13) = 0
(-2/13)*b-3*b^2+4/13 = 0
4/13-3*b^2-2/13*b = 0
DELTA = (-2/13)^2-(-3*4/13*4)
DELTA = 628/169
DELTA > 0
b = ((628/169)^(1/2)+2/13)/(-3*2) or b = (2/13-(628/169)^(1/2))/(-3*2)
b = ((628/169)^(1/2)+2/13)/(-6) or b = (2/13-(628/169)^(1/2))/(-6)
b in { ((628/169)^(1/2)+2/13)/(-6), (2/13-(628/169)^(1/2))/(-6) }
| (27a^3)-(8b^6)= | | P=3w+9forw | | 6x+3y=90 | | 3a^2-21a= | | 4x-4=(-16) | | 2y=25y+13 | | 4w-2+2(w+1)= | | 3x+y+z=30 | | x+5/3x=40 | | 5(2w-7)=6w+3 | | (4x+5)=(3x+15) | | .05x-3.1=9 | | 3(x+1)-8=2(3x-4) | | 12.5=x+x+4x+4x | | 4x+4=6x-15 | | X+4y-2z=24 | | 2x/3-x/5=7 | | (2y)^5/2 | | 3x+13=91 | | 3x-13=19+7x | | 5=r/2 | | 5x+9y-z=88 | | 3x+16=85 | | 2.5m+8=23 | | 5/2a=-25 | | -5k=3k-24 | | 3(1-2t)-2=16+3t | | 2(x+3)=-4(x+5) | | 8z^2-68z=32 | | 576/x=0 | | 3x-8+7x=12+9x-3 | | 3x^3y^2+5xy^4=0 |