Question 331561
{{{(3sqrt(5)-9sqrt(7))(2sqrt(5)+6sqrt(7))}}}foil 
<p>
{{{(3sqrt(5))(2sqrt(5))+(3sqrt(5))(6sqrt(7))+(-9sqrt(7))(2sqrt(5))+(-9sqrt(7))(6sqrt(7))}}} multiply
<p>
{{{(6sqrt(25))+(18sqrt(35))+(-18sqrt(35))-(54sqrt(49))}}} factor and cancel
<p>
{{{(6*5)+cross(18sqrt(35))+cross(-18sqrt(35))-(54*7))}}}
<p>
{{{(6*5)-(54*7)}}} multiply
<p>
{{{(30)-(378)}}} subtract
<p>
{{{highlight(-348)}}}