0.25=(10.8)(240)/d^2

Solution for 0.25=(10.8)(240)/d^2 equation:

D( d )

d^2 = 0

d^2 = 0

d^2 = 0

1*d^2 = 0 // : 1

d^2 = 0

d = 0

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

0.25 = (10.8*240)/(d^2) // - (10.8*240)/(d^2)

0.25-((10.8*240)/(d^2)) = 0

0.25-2592*d^-2 = 0

-2592*d^-2 = -0.25 // : -2592

d^-2 = 0.00009645

-2 < 0

1/(d^2) = 0.00009645 // * d^2

1 = 0.00009645*d^2 // : 0.00009645

10368.06635562 = d^2

d^2 = 10368.06635562 // ^ 1/2

abs(d) = 10368.06635562^(1/2)

d = 10368.06635562^(1/2) or d = -10368.06635562^(1/2)

d in { 10368.06635562^(1/2), -10368.06635562^(1/2) }