Question 517495
{{{ 3/(x+7) + 4/(x-8) }}}
.
First consider the equivalent form:
.
{{{ a/b + c/d = (ad+bc)/bd }}}
.
Then substitute.
.
{{{ a = 3 }}}
{{{ b = (x+7) }}}
{{{ c = 4 }}}
{{{ d = (x-8) }}}
.
{{{ (ad + bc) /bd = ( 3* (x-8) + (x+7)*4 ) / ( (x+7)(x-8) ) = (7x+4)/ ( (x+7)(x-8) ) }}}