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)
(1/5)*x-((9/10)*x) = 15-71 // - 15-71
(1/5)*x-((9/10)*x)-15+71 = 0
(1/5)*x+(-9/10)*x-15+71 = 0
56-7/10*x = 0 // - 56
-7/10*x = -56 // : -7/10
x = -56/(-7/10)
x = 80
x = 80
| x^14=729 | | 5+2x=2x+6 | | 92=2r-7 | | 3y-30+1=-2-8x | | 14/15-3/5= | | 100x-25=25 | | 16cos^2x=7 | | 6(x-6.6)=4.2 | | 4u-9=3u+9 | | 5v+3-3v=-7 | | 450=15x+455 | | 9=3(t-7) | | 5(x-3.8)=8.5 | | 8x+4x+14=5x+6x-13 | | 5678(h*7)=5648(h*9) | | 0.1(x+10)-0.08(x-30)=3 | | 2.4x+2.4=4.2 | | ih+09=89 | | h+j-56j=h+5 | | n-3n=14-4m | | 4/8-2=1 | | 2x+4y=3x+2y | | 13=u-(-6) | | 6(7-2)=58 | | 7-(-19)= | | 4=8-2h | | h=32^2/64 | | 9=v^2/64 | | 3yi=9iy | | 6y+20=5 | | 7x+56=2x-4 | | 3yi=9i |