Question 163960
subtract, write answer in lowest terms:
in words it would be 9x over x2-49 minus 5 over 7-x
:
{{{(9x)/((x^2-49))}}} - {{{5/((7-x))}}}
:
Note that (x^2-49) is the "difference of squares, factor:
Change the signs in (7-x) multiply by -1
{{{(9x)/((x-7)(x+7))}}} - {{{5/(-1(x-7))}}}
Which is:
{{{(9x)/((x-7)(x+7))}}} + {{{5/((x-7))}}}
:
The common denominator
{{{(9x + 5(x+7))/((x+7)(x-7)))}}} = {{{((9x + 5x + 35))/((x+7)(x-7)))}}} = {{{(14x + 35)/((x+7)(x-7)))}}} = {{{(7(2x + 5))/((x+7)(x-7)))}}}