If it's not what You are looking for type in the equation solver your own equation and let us solve it.
A in (-oo:+oo)
12*A-((30/6)*A^2)-(9*A) = 0
12*A-5*A^2-9*A = 0
3*A-5*A^2 = 0
DELTA = 3^2-(-5*0*4)
DELTA = 9
DELTA > 0
A = (9^(1/2)-3)/(-5*2) or A = (-9^(1/2)-3)/(-5*2)
A = 0 or A = 3/5
A in { 0, 3/5 }
| 4x^3=48 | | 8x+12=2x-18 | | 2.3*3.5= | | 3a^2=-3a+3 | | 2/3n=x/-3 | | 4x*lnx+x=0 | | x+5=46/11 | | B+6-3b=-2 | | 2n+15=4n+21 | | -23=-10+-2a+a | | 12-2c=3c+3 | | 3x(2x+1)(x+10)=0 | | 2a-4=8a+44 | | -6+22d-2d=4 | | 3-n=-8 | | n/4*n/3=1/2 | | -16t^2+40t-2.5=0 | | 5x-25=-15x-5x+25 | | -16t^2+40t+2.5=0 | | 7h-21=86+2 | | 555x+5=2210 | | 26-(4+6)/2-1+15/3 | | 555x+5=1120 | | 555x+5=1 | | 6+6x=1/2 | | g^2+2g-143=0 | | (8x+12)/(x^2+5x+4) | | 5*1/9+8/23/184/24-2 | | 4.2*0.003= | | 0.7x^2-28x+12000=11790 | | -6(16-7)= | | 290+x/5=70 |