SOLUTION: 2x^3 - 10 + 4x^2 - 5x Factor by grouping

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Question 419328: 2x^3 - 10 + 4x^2 - 5x
Factor by grouping
Found 2 solutions by ewatrrr, duckness73:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

Factoring by grouping

2x^3 - 10 + 4x^2 - 5x

2x^3  + 4x^2 - 5x - 10

 2x^2(x+2) - 5(x+2)

(2x^2 -5)(x+2)

Answer by duckness73(47) About Me  (Show Source):
You can put this solution on YOUR website!
First, let's rearrange the terms:
2x%5E3+-+10+%2B+4x%5E2+-+5x = 2x%5E3+%2B+4x%5E2+-+5x+-+10
Now, lets take 2x%5E2 out of the first two terms:
2x%5E3+%2B+4x%5E2+-+5x+-+10 = 2x%5E2(x + 2) - 5x - 10
Now, lets take out -5 from the second two terms:
2x%5E2(x + 2) - 5x - 10 = 2x%5E2(x + 2) - 5(x + 2)
Notice now that x + 2 is a factor in both terms, so we can factor that out, too:
(x + 2)(2x%5E2 - 5)
There's your factoring by grouping.