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)
12 = (4/5)*x // - (4/5)*x
12-((4/5)*x) = 0
(-4/5)*x+12 = 0
12-4/5*x = 0 // - 12
-4/5*x = -12 // : -4/5
x = -12/(-4/5)
x = 15
x = 15
| -5(n+2)+13=2n-15 | | 2(7-x)-4(x+3)=32-x | | 6x+260=15x-10 | | 2*6=4 | | 5m-3=4m+5 | | 2y=-0-4 | | 2x=-4*-2+-0.5x-8 | | 5x+7-2=35 | | 4-(x+3)= | | 18-5v=2v+4 | | 18v-5v=2v+4 | | 14e^2x+e^2x=975 | | 7x+9=50 | | 4x+50=370 | | x^4+x^2-25=0 | | gm-2=13 | | 2x^2-8x+x-4= | | 5x/6-4x/9 | | x-11=-30 | | -20-20x=10-7x | | -X(X+3)+2X-1=6 | | 3000-p+60=2050 | | 15x-9=15x+9 | | x^5+2x^4y-35x^3y^2-3x^4+15x^3y=0 | | 5x+1+8=7-2 | | ln(7/x)=56.626 | | ln(7/k)=56.626 | | 18s=162 | | 8x+(5x-6-4x-1)=x-(x-4) | | (2.6-y)/2.6=0.14 | | 80s=2000000 | | 5s=225 |