Posted by **Julie** on Wednesday, January 23, 2013 at 4:17pm.

Can someone help me factor this 5x^2+8x+9

What's the technique in factoring

- Math -
**Steve**, Wednesday, January 23, 2013 at 4:57pm
just a lot of experience, some guesses, and some luck. You know from looking at it that the factors will be of the form

(5x+a)(x+b)

where the two a,b are one each of 1,9.

You need 5b+9a = 8

Now, even a cursory look assures you that there are no such a,b both positive where this can be the case.

A quick check of the discriminant shows that it is 8^2-4*9*5 = 64-180 < 0, so there are no real roots. That means no factors over the rationals.

Is there a typo here? The beast can certainly not be factored.

## Answer this Question

## Related Questions

- FACTORING - I can't figure out how to factor this. I know you use the technique ...
- math - What factoring technique would be used to factor 2x^2+5x+3?
- math - Can someone please help me with this factoring? Thanks! Factor 3x^2-7xy+...
- factoring,math - can someone show me how to factor this: i keep getting -6 and 5...
- factoring - I cannot figure these out.Can someone Factor completely: 3x2 - x - 4...
- math,correction - can someone check these for me please.... problem#4 Directions...
- factor the trinomial by grouping - 15x^3-9x^2-6x Can someone please show me how ...
- factoring - Factor x3 + 9x2 + 27x + 27 Factor 8a3 + 60a2b + 150 ab2+ 125b3 I ...
- Factoring - x2(squared)-4x+4 I would factor this into (X - 2)(X - 2) If you don'...
- Gr.11 Factoring - hi, could someone please explain how to factor this? 3x^2-2xy-...

More Related Questions