Question 351932
{{{(3/sqrt(5) - 9/sqrt(2))(2/sqrt(5) + 6/sqrt(2))}}}
Just use FOIL (or whatever technique you have learned for multiplying binomials (two term expressions)):
{{{(3/sqrt(5))*(2/sqrt(5)) + (3/sqrt(5))(6/sqrt(2)) - (9/sqrt(2))(2/sqrt(5)) - (9/sqrt(2))(6/sqrt(2))}}}
Multiplying out these fractions we get:
{{{6/5 + 18/sqrt(10) - 18/sqrt(10) -54/2}}}
The square root terms cancel out and 54/2 = 27 leaving:
{{{6/5 -27}}}
Subtracting:
{{{6/5 - 135/5}}}
{{{-129/5}}}
As a mixed number this is
{{{-25&4/5}}}