3(30/s)=4(s/19)

Solution for 3(30/s)=4(s/19) equation:

D( s )

s = 0

s = 0

s = 0

s in (-oo:0) U (0:+oo)

3*(30/s) = 4*(s/19) // - 4*(s/19)

3*(30/s)-(4*(s/19)) = 0

(-4/19)*s+3*(30/s) = 0

90*s^-1-4/19*s^1 = 0

(90*s^0-4/19*s^2)/(s^1) = 0 // * s^2

s^1*(90*s^0-4/19*s^2) = 0

s^1

(-4/19)*s^2+90 = 0

(-4/19)*s^2+90 = 0

DELTA = 0^2-(4*90*(-4/19))

DELTA = 1440/19

DELTA > 0

s = ((1440/19)^(1/2)+0)/(2*(-4/19)) or s = (0-(1440/19)^(1/2))/(2*(-4/19))

s = -19/8*(1440/19)^(1/2) or s = 19/8*(1440/19)^(1/2)

s in { -19/8*(1440/19)^(1/2), 19/8*(1440/19)^(1/2)} 

s in { -19/8*(1440/19)^(1/2), 19/8*(1440/19)^(1/2) }