SOLUTION: (radical7 + 2)(radical7 - 5) solve using foil

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Question 257293: (radical7 + 2)(radical7 - 5) solve using foil
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
First:sqrt%287%29sqrt%287%29=7+
Outer:sqrt%287%29%2A%28-5%29=-5%2Asqrt%287%29
Inner:2%2Asqrt%287%29=2%2Asqrt%287%29
Last: %282%29%28-5%29=-10
Then add it all together,
%28sqrt%287%29%2B2%29%28sqrt%287%29-5%29=7-5%2Asqrt%287%29%2B2%2Asqrt%287%29-10
%28sqrt%287%29%2B2%29%28sqrt%287%29-5%29=-3-3%2Asqrt%287%29
%28sqrt%287%29%2B2%29%28sqrt%287%29-5%29=-3%281%2Bsqrt%287%29%29