SOLUTION: Perform the indicated operations and simplify: z-7/z-9 - z+1/z+9 + z-45/z^2-81 I came up with 3/z+9 Multiply. (5sqrt2 - 10sqrt5)(3sqrt2 + 6sqrt5) Multiply and simplify by

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Perform the indicated operations and simplify: z-7/z-9 - z+1/z+9 + z-45/z^2-81 I came up with 3/z+9 Multiply. (5sqrt2 - 10sqrt5)(3sqrt2 + 6sqrt5) Multiply and simplify by       Log On


   

Question 353584: Perform the indicated operations and simplify:
z-7/z-9 - z+1/z+9 + z-45/z^2-81
I came up with 3/z+9
Multiply.
(5sqrt2 - 10sqrt5)(3sqrt2 + 6sqrt5)
Multiply and simplify by factoring. Assume that all expressions under radicals represent nonnegative numbers.
^3sqrtY^7 ^3sqrt16Y^8
Any help is very much appreciated. Thank you in advance.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
First one: You have an addition error somewhere. The answer should be highlight_green%2811%2F%28z%2B9%29%29.
Check your work to see if you can spot the error.
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%285%2Asqrt%282%29+-+10%2Asqrt%285%29%29%283%2Asqrt%282%29+%2B+6%2Asqrt%285%29%29
Use the FOIL method,

%285%2Asqrt%282%29+-+10%2Asqrt%285%29%29%283%2Asqrt%282%29+%2B+6%2Asqrt%285%29%29=30-300

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