If it's not what You are looking for type in the equation solver your own equation and let us solve it.
f in (-oo:+oo)
-20 = (5/9)*(f-32) // - (5/9)*(f-32)
-((5/9)*(f-32))-20 = 0
(-5/9)*(f-32)-20 = 0
-5/9*(f-32)-20 = 0
-5/9*(f-32)-20 = 0
-5/9*f-20/9 = 0
-5/9*f-20/9 = 0
-5/9*f-20/9 = 0 // + 20/9
-5/9*f = 20/9 // : -5/9
f = 20/9/(-5/9)
f = -4
f = -4
| 22/9*15/52*8/55 | | (6-v)(5v-2)=0 | | 12=3+9(x-2) | | 11*33x= | | -180-12x=90+6x | | -7/9t=-5/12 | | 20x=30y-45000 | | 7(.05)+3(.6)=10x | | -2(X+1)=-18-5X | | 6(x-1)=x-21 | | 112x=3x | | v=V+gt | | 3y+4+5y-2=42 | | 6x^2+17=77 | | 5w+8-12w=16w-15w | | 1x+4=4x+2 | | 6*(w-8)+16=4 | | 21/15=7/x | | 2x-8+1+4x=0 | | 2(4x+8)=-16 | | 175m-75m+52250=55825-175m | | 4x+5+2x-20=8x | | x-8.7=-5.6 | | 3x^2=38 | | 25(5b+11)=19 | | -15+3x-7x=(-43) | | 7-27= | | 3/4-1/4z=1/4 | | 25.2/10 | | 2(2x-7)+4=-8 | | 4x^2+39x=10 | | 2*Log[9](x)=Log[9](x+4)+Log[9](2) |