Question 27470
7x^2 + 6x from 9x^2 - 3 
{{{(9x^2-3) - (7x^2 +6x)}}}
{{{ 9x^2+0x-3}}}
 {{{-7x^2 -6x+0}}}    *sign changed
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 {{{ 2x^2 -6x -3}}}