SOLUTION: Hello, I am really having trouble with these radical expressions. Here is another one I cannot solve. I think I should use the foil method, but am not sure I am doing it right,

Algebra ->  Radicals -> SOLUTION: Hello, I am really having trouble with these radical expressions. Here is another one I cannot solve. I think I should use the foil method, but am not sure I am doing it right,       Log On


   

Question 43640: Hello, I am really having trouble with these radical expressions. Here is another one I cannot solve. I think I should use the foil method, but am not sure I am doing it right, can someone please help me..
(5√[3]+√[5])(√[3]–2√[5])
Here I tried to put it together but am just totally stuck at this point. I think I combined them the right way, but I just do not understand how to proceed from here.
5√3√3-5√32√5+√5√3-2√5√5
Any help that can be provided will be greatly appreciated.
Thanks....
Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
(5√[3] + √[5])(√[3] – 2√[5])
5√[9] + √[5]√[3] - 10√[15} - 2√[25]
5(3) + √[15] - 10√[15] - 2(5)
15 - 10 + √[15] - 10√[15]
5 - 9√[15]