## Rell25 2 years ago 5x^2+3x+8=0

1. growdabone

whaddya need done? solving for "x" or something else?

2. mew55

i believe u have to use the quadratic formula

3. mew55

i am getting -154 under the square root :/

4. mew55

but this is +3, where is the 3? the only way to get the 3 is 5-8

5. mew55

sorry 8-5

6. ChristianGeek

Oops, my bad! Let me rewrite.

7. mew55

I believe this is a quadratic formula problem but the inside of the square root gave me

8. Rell25

Find the product of the solution of this equation

9. mew55

|dw:1354209002036:dw|

10. mew55

|dw:1354209128299:dw|

11. Rell25

$5x^2+3x+8=0$

12. ChristianGeek

Sorry, I was not paying attention in my deleted response (see how easy it is to go too quickly and get it wrong?!). @mew55 is correct...you do need the quadratic formula: $x = \frac{-b \pm \sqrt{b^{2} - 4ac}}{2a} = \frac{-3 \pm \sqrt{3^{2} - 4(5)(8)}}{2(5)} = \frac{-3 \pm \sqrt{9 - 160}}{10} = \frac{-3 \pm \sqrt{151}}{10}$ 151 is a prime number, so you can't simplify any more than that without a calculator.

13. mew55

does the 'i' needs to be simplify since the inside of the square root is -151?

14. mew55

and its okay XD

15. ChristianGeek

Forgot the negative in the final square root...should be: $\frac{-3 \pm \sqrt{-151}}{10}$

16. ChristianGeek

@mew55...you could: $\frac{-3 \pm \sqrt{151}(i)}{10}$

17. mew55

yep. that is wut i was thinking. XD X3

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