SOLUTION: Solve each equation W^3 + 5w^2 - W = 5

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Question 35565: Solve each equation
W^3 + 5w^2 - W = 5
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Set this equation equal to zero and factor by grouping the first two and last two terms of it.

W%5E3+%2B+5w%5E2+-+W+=+5
W%5E3+%2B+5w%5E2+-+W+-+5+=+0

Group the first two and the last two:
w%5E2%28w%2B5%29+-1%28w%2B5%29+=+0+
%28w%2B5%29+%28+w%5E2+-1%29+=+0
+%28w%2B5%29+%28w-1%29%28w%2B1%29+=+0
w=-5, w=1, w=+-1

As you might expect with an equation with an x^3, there will be 3 solutions.

R^2 at SCC