## Preetha one year ago What is the best way to solve this quadratic: x2 + 3x – 4 = 0

1. Preetha

@ganeshie8

2. AlexandervonHumboldt2

hmm it looks like only quadratic formula is the best way

3. anonymous

Well I guess it would be best first to check with the discriminant :P

4. mathmate

I suggest factoring.

5. AlexandervonHumboldt2

yeah

6. ganeshie8

quadratic formula ofcourse! |dw:1444068957844:dw|

7. AlexandervonHumboldt2

lets listen to ganishe

8. just_one_last_goodbye

WAIT!!! let me have a try please ^_^

9. AlexandervonHumboldt2

yeah preetha substitute the values using the quadratic formula solve the equation

10. just_one_last_goodbye

x2 + 3x – 4 = 0 Refine: 5x - 4 = 0 Add 4 to both sides: 5x - 4 + 4 = 0 + 4 5x=4 Divide both sides by 5: $\frac{ 5x }{ 5 } = \frac{ 4 }{ 5 }$ Answer: $x = \frac{ 4 }{ 5 }$

11. AlexandervonHumboldt2

The quadratic formula is (-b+-sqrt(b^2 - 4ac))/2a where ax^2+bx+c=0 a=1 b=3 c=-4 substitute values and solve;

12. AlexandervonHumboldt2

@just_one_last_goodbye you gave an answer lol coc lol

13. just_one_last_goodbye

Pfft I gave the answer why? because c;' I know @Preetha is very smart to already know the answer

14. Preetha

That is fine, I do have a couple of strategies now to use. And I do understand this. Thanks all for jumping in.

15. AlexandervonHumboldt2

yeahhhhh i know k jk

16. imqwerty

best way is to use common sense :) we can easily see that x=1 is a root and sum of roots is -b/a =3 so 1 root is1 another will be 3-1=2

17. Preetha

Its actually fascinating how you all have different strategies to solve this - that is very good to know.

18. just_one_last_goodbye

No problem Mrs. Ram ^-^ Do I get at least 5 owl bucks? I always wanted to know what it would look like on my account

19. imqwerty

(:

20. just_one_last_goodbye

~sigh~ . - .

21. just_one_last_goodbye

WEE THE OWL BUCKS ;-; omg... thank you so much <3 I love u guys so much...

22. imqwerty

oops i did a silly mistake sum of roots ==> -b/a=-3 and one root is 1 so other root is -4

23. Nnesha

it's $\huge\rm x^2+3x-4=0$ x squared not 2x+3x :=) squared that's what makes it quadratic :=) just_one_last :=)

24. Nnesha

as suggested above factoring would be great and AC (headphone :P ) method the best!

25. anonymous

Preetha is asking a question!!!??? OMG! The world is ending!!!

26. Jaynator495

|dw:1444693788595:dw| Click the sphere.

27. Jaynator495

|dw:1444693919314:dw| Or click anywhere on this canvas

28. Jaynator495

$$\color{#0cbb34}{\text{Originally Posted by}}$$ @jinxhead20 Preetha is asking a question!!!??? OMG! The world is ending!!! $$\color{#0cbb34}{\text{End of Quote}}$$ not the first time, she can often be found asking questions to take notes on how people answer them :P

29. TheSmartOne

Unfortunately, x2 + 3x – 4 = 0 is not a quadratic equation.