Question 889759
Solve the system of equations using elimination
{{{9p + 7q = 16}}}
{{{7p - 5q = 25}}}

Start by eliminating one variable.
{{{9p + 7q = 16}}}(7)
{{{7p - 5q = 25}}}(-9)

{{{ 63p  + 49q = 122}}}
{{{-63p  + 45q = -255}}}
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{{{94q = -133}}}
{{{q = (-133/94)}}}

Now eliminate the other variable.  
{{{9p + 7q = 16}}}(5)
{{{7p - 5q = 25}}}(7)

{{{45p + 35q = 80}}}
{{{49p - 35q = 175}}}
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{{{94p = 255}}}
{{{p = (255/94)}}}

The solutions are {{{ q = (-133/94) }}} and {{{p = (255/94) }}}