If it's not what You are looking for type in the equation solver your own equation and let us solve it.
D( t )
18-(9*t) = 0
18-(9*t) = 0
18-(9*t) = 0
18-9*t = 0
18-9*t = 0 // - 18
-9*t = -18 // : -9
t = -18/(-9)
t = 2
t in (-oo:2) U (2:+oo)
4*t^2-((8*t)/(18-(9*t))) = 0
4*t^2-8*t*(18-9*t)^-1 = 0
(-8*t)/(18-9*t)+4*t^2 = 0
(-8*t)/(18-9*t)+(4*t^2*(18-9*t))/(18-9*t) = 0
4*t^2*(18-9*t)-8*t = 0
72*t^2-36*t^3-8*t = 0
72*t^2-36*t^3-8*t = 0
4*t*(18*t-9*t^2-2) = 0
18*t-9*t^2-2 = 0
DELTA = 18^2-(-9*(-2)*4)
DELTA = 252
DELTA > 0
t = (252^(1/2)-18)/(-9*2) or t = (-252^(1/2)-18)/(-9*2)
t = (6*7^(1/2)-18)/(-18) or t = (-6*7^(1/2)-18)/(-18)
4*t*(t-((6*7^(1/2)-18)/(-18)))*(t-((-6*7^(1/2)-18)/(-18))) = 0
(4*t*(t-((6*7^(1/2)-18)/(-18)))*(t-((-6*7^(1/2)-18)/(-18))))/(18-9*t) = 0
(4*t*(t-((6*7^(1/2)-18)/(-18)))*(t-((-6*7^(1/2)-18)/(-18))))/(18-9*t) = 0 // * 18-9*t
4*t*(t-((6*7^(1/2)-18)/(-18)))*(t-((-6*7^(1/2)-18)/(-18))) = 0
( 4*t )
4*t = 0 // : 4
t = 0
( t-((-6*7^(1/2)-18)/(-18)) )
t-((-6*7^(1/2)-18)/(-18)) = 0 // + (-6*7^(1/2)-18)/(-18)
t = (-6*7^(1/2)-18)/(-18)
( t-((6*7^(1/2)-18)/(-18)) )
t-((6*7^(1/2)-18)/(-18)) = 0 // + (6*7^(1/2)-18)/(-18)
t = (6*7^(1/2)-18)/(-18)
t in { 0, (-6*7^(1/2)-18)/(-18), (6*7^(1/2)-18)/(-18) }
| 4+1/7+1/2 | | 18-n=9+3 | | -3.5x=12.25 | | 21-6=11 | | 7c=-42 | | 2+3x=7+3x | | 6x+9x-23=115-8x | | 8x+35=47 | | -4(3t-5)+8t=7t-5 | | 8/h=288 | | 10+17c+13c= | | -x-4=-13 | | b-24=16 | | 2/1/3+1/1/4 | | 19x+6y=71.90 | | x=4x-8/(x-4)(x+1) | | 4.2x-3=0.5 | | -9(x+12)=8(4+5x)-4x | | 15+10z+14-11z= | | -7+21=-4x | | m/4+m/3 | | (3+y)/4=-y/8 | | 2(15+10.5x)=11x | | 1/5/55/6 | | y=11x^2+24x+4 | | 12-3(x+7)=15 | | 13=9m+5 | | -4x+13+5x=4+x+9 | | 2.20+x=3.50 | | 25(1-x)=125 | | 15x-4=27x+4 | | 5x+7-4x=4 |