SOLUTION: Solve by any method 3y^4=28y^2-9

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Question 384896: Solve by any method
3y^4=28y^2-9
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,         

solving

3y^4=28y^2-9

3y^4 - 28y^2+ 9 = 0

Factoring

(3y^2 -1)(y^2 - 9)= 0 Note: inner and outer products = -28y^2

(3y^2 -1)= 0

  y^2 = 1/3

  y = ± sqrt%281%2F3%29 Or ± sqrt%283%29/3

(y^2 - 9)= 0 

  y^2 = 9

  y =  ± 3