Question

Just want help doing it! Don't want you to give me the answer.
What are the solutions of 3x2 + 4x = –5?

Answer 1

is 3x2 3 times 2?

Answer 2

or 3x (times) 2?

Answer 3

add 5 to both sides to make it equal to zero
tell me what you get

Answer 4

sorry 3x^2

Answer 5

ohhh :O

Answer 6

You know this is your 5th question like that . Every now and then, its good to try something yourself

Answer 7

3x^2+4x+5=0 @Jim766
@Luis_Rivera I have done alot myself. I am just asking for help to understand scene I have to learn this all on my own with out a teacher if you got a problem with me asking questions on getting help then don't look at my stuff!

Answer 8

You can't factor, so you'll have to use the quadratic formula

\[\Large x=\frac{-b \pm \sqrt{b^2-4ac}}{2a}\]

in this case

a = 3
b = 4
c = 5

Answer 9

in problems like this just set the function to 0 and use quadratic formula

Answer 10

the answer will not be real....b^2 - 4ac is negative

are you sure you copied the problem correctly?

Answer 11

@jim_thompson5910 & @galacticwavesXX well I'm stuck here I crossed out two answers but i got two left but I don't understand. \[\frac{-4 \pm \sqrt{4^2-4(3)(5)}} {2(3)}\] = \[\frac{-4 \pm \sqrt{16-60}} {6}\] =\[\frac{-4 \pm \sqrt{44}} {6}\] and this is where i'm stuck. Answer are- A.\[\frac{-4 \pm i\sqrt{66}} {6}\] B. \[\frac{-2 \pm 2i\sqrt{66}} {3}\] c.\[\frac{-2 \pm i\sqrt{11}} {3}\] D. \[\frac{-4 \pm i\sqrt{11}} {6}\] What do i do from here?

Answer 12

You should be getting this


\[\Large x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}\]


\[\Large x = \frac{-(4)\pm\sqrt{(4)^2-4(3)(5)}}{2(3)}\]


\[\Large x = \frac{-4\pm\sqrt{16-(60)}}{6}\]


\[\Large x = \frac{-4\pm\sqrt{-44}}{6}\]


Does that help?

Answer 13

That's not the final answer, but it will eventually get you there

Answer 14

how did you get -44?

Answer 15

16 - 60 = -44

Answer 16

yeah nevermind I subtracted wrong lol. But how do I go from here?

Answer 17

well

\[\Large \sqrt{-44} = \sqrt{-1*44}\]

\[\Large \sqrt{-44} = \sqrt{-1*4*11}\]

\[\Large \sqrt{-44} = \sqrt{-1}*\sqrt{4}*\sqrt{11}\]

\[\Large \sqrt{-44} = i*2*\sqrt{11}\]

\[\Large \sqrt{-44} = 2i*\sqrt{11}\]

Answer 18

So

\[\Large x = \frac{-4\pm\sqrt{-44}}{6}\]

turns into

\[\Large x = \frac{-4 \pm 2i*\sqrt{11}}{6}\]

Answer 19

So then would the answer be C?

Answer 20

yes

Answer 21

correct, it's C

Answer 22

Okay thank you :)

Answer 23

yw

Answer 24

3x2+4x+5=0
X=(-b±√(b^2-4ac))/2a
X=(-4±√(4^2-4*3*5))/(2*3)
X=(-4±√(16-60))/6
X=(-4±√(-44))/6
X=(-4±2×11i)/6
X=(-4)/6±22i/6
X=(-2)/3±11i/3