Question 309366
Simplify 4x+12/3x * 6x/x^2-9

doing 2 simplify solutions to be sure which one you meant:
simplify 4x + 12/(3x) * 6x/(x^2) - 9
{{{ 4x + 12/(3x) * 6x/(x^2) - 9 }}}
{{{ 4x + 72x/(3x^3) - 9 }}}
{{{ 4x + 24/(x^2) - 9 }}}
(divided middle term by (3x/3x))
{{{ 4x * (x^2/(x^2)) + 24/(x^2) - 9 * (x^2/(x^2)) }}}
{{{ 4x^3/(x^2) + 24/(x^2) - 9x^2/(x^2) }}}
{{{ (4x^3 - 9x^2 + 24)/(x^2) }}}
simplify (4x + 12)/3x * 6x/(x^2 - 9)
{{{ (4x + 12)/3x * 6x/(x^2 - 9) }}}
{{{ (4x + 12)6x/(3x(x^2 - 9)) }}}
factor
{{{ 4(x + 3)6x/(3x(x + 3)(x - 3)) }}}
{{{ 4(6x)/(3x(x - 3)) }}}
{{{ (4*2)/(x - 3) }}}
(divided by (3x/3x))
{{{ 8/(x - 3) }}}