SOLUTION: 188.) (7xy˛-10y)(7xy˛+10y) 221.) (xy+ab˛)(xy-ab˛) simplify....thanks

Algebra ->  Expressions -> SOLUTION: 188.) (7xy˛-10y)(7xy˛+10y) 221.) (xy+ab˛)(xy-ab˛) simplify....thanks       Log On


   

Question 175957: 188.) (7xy˛-10y)(7xy˛+10y)

221.) (xy+ab˛)(xy-ab˛)
simplify....thanks
Found 2 solutions by stanbon, checkley75:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
These both follow the pattern (a-b)(a+b) = a^2-b^2
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(7xy˛-10y)(7xy˛+10y) = (7xy^2)^2 - (10y)^2 = 49x^2y^4 - 100y^2
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221.) (xy+ab˛)(xy-ab˛)
= (xy)^2 - (ab^2)^2 = x^2y^2 - a^2b^4
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Cheers,
Stan H.

Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
188.)
7xy˛-10y
7xy˛+10y
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49x^2y^4-100y^2 ans.

221.)
xy+ab˛
xy-ab˛
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x^2y^2-a^2b^4 ans.