How do I factor 4x^2+18x-10?
Yes, it can be factored. I would start by factoring out the common factor of 2, then use whatever method you are familiar with for factoring a trinomial.
If you need help with that, please show your work as far as you get, so we can see your method and guide you along.
NO. Should be: 2(2x^2 + 9x - 5) ; got that?2x + 9x -5, box method won't work.
b=9 | ac=-10 |
10 + -1 =9 | 10*-1=-10 |
Is this what you mean by the "box method"?
Why not? That method says that you need factors of (2)(-5) = -10 that will add up to +9. Since you're multiplying to a negative, one factor will be positive and one will be negative. Since you're adding to a positive, the larger factor (in absolute-value terms) will get the "plus" sign, and the factors will need to be nine units apart.2x + 9x -5, box method won't work.