How do you factor 10x^2+15x-70?
2 Answers
The correct factoring is
Explanation:
We can start getting rid of a
5(2x^2 + 3x - 14)
Now we rewrite as
5(2x^2 - 4x + 7x - 14)
Which is equivalent as
5(2x(x - 2) + 7(x - 2))
We can now factor out
5(2x + 7)(x - 2)
If we try expanding this we see
5(2x^2 + 7x - 4x - 14)
10x^2 + 15x - 70
Which is what we had at first, so the factoring is correct.
Hopefully this helps!
10x^2+15x-70=5(2x+7)(x-2)
Explanation:
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Take out the common factor of 5 to give: 5(2x^2+3x-14)
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You know that the brackets will next look like this:
5(2x ± ??)(x ± ??) -
You need to determine what two numbers when multiplied will equal -14 and will fit in with the 2x. A quick bit of trial and error shows that the numbers that will fit are +7 and -2 which gives: 5(2x+7)(x-2)