SOLUTION: Here is a sample problem similar to the one I am having trouble with: (6+4{{{sqrt(7)}}})(6-4{{{sqrt(7)) and this was my attempt: (6+4{{{sqrt(7)}}})(6-4{{{sqrt(7)}}})=6^(2)

Algebra ->  Radicals -> SOLUTION: Here is a sample problem similar to the one I am having trouble with: (6+4{{{sqrt(7)}}})(6-4{{{sqrt(7)) and this was my attempt: (6+4{{{sqrt(7)}}})(6-4{{{sqrt(7)}}})=6^(2)      Log On


   

Question 260213: Here is a sample problem similar to the one I am having trouble with:
(6+4sqrt%287%29)(6-4sqrt%287%29%29%0D%0A%0D%0Aand+this+was+my+attempt%3A%0D%0A%0D%0A%286%2B4%7B%7B%7Bsqrt%287%29)(6-4sqrt%287%29)=6^(2)-sqrt%287%29^(2)=36-7=29
(Correct answer is -76) But I am not sure how to get there.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
(6+4sqrt%287%29)(6-4sqrt%287%29%29%0D%0A%0D%0Aand+this+was+my+attempt%3A%0D%0A%0D%0A%286%2B4%7B%7B%7Bsqrt%287%29)(6-4sqrt%287%29)=6^(2)-sqrt%287%29^(2)=36-7=29
(Correct answer is -76)
-------------------------------
You show 3 binomials, I think there should be 2, and you left out the 4.
---------------
+%286%2B4sqrt%287%29%29%2A%286-4sqrt%287%29%29+
= 6%5E2+-+%284sqrt%287%29%29%5E2
= 36 - 16*7 = 36 - 112
= -76