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)
12/20 = x/35 // - x/35
12/20-(x/35) = 0
3/5-1/35*x = 0 // - 3/5
-1/35*x = -3/5 // : -1/35
x = -3/5/(-1/35)
x = 21
x = 21
| 8/x+240 | | 52+x=75 | | 14-(3*a)=28 | | 4x^2y-3xy^2+15xy-12+9xy^2-14xy+19=13x^2y+7xy^2-16xy+21 | | 7x+2y=107 | | 8.27x=4.82 | | 5+3*a=23 | | 8.27=4.82 | | -4-5r=-4-6r | | 12-6*a=6 | | 3/2(z+5)-1/4(z+24)=0 | | 4d+3=23 | | -7p-10=-8p-4q | | m^2+12m=35 | | 11-8*a=13 | | 4(3y^2-7y+4)-1=0 | | -20+25x^2-5x^4=0 | | 5-3m/3=4-5m/4 | | 6x+15=57 | | 19y-60=4(y+15) | | 2t-5g+2.3=-18.8 | | 14+9y+1=42 | | 64x^2-100=0 | | 3+8x=67 | | 27=4k-9 | | 2(4+0.5x)+3=10 | | 80-7x=38+15 | | 11-7x=155-35x | | 23=4d-5 | | 13=3a-5 | | 3(15-t)=3(5+t) | | x+12.5=-3.5x |