## thisisarri 2 years ago Which part of the quadratic formula tells you whether the quadratic equation can be solved by factoring? −b b2 − 4ac 2a Use the part of the quadratic formula that you chose above and find its value given the following quadratic equation: 2x2 + 7x + 3 = 0

1. klimenkov

What do you think about it?

2. thisisarri

i think its the middle one

3. klimenkov

Why so you think so? Or you just guess?

4. thisisarri

well, i think you need that to factor, but its pretty much just a guess

5. thisisarri

why, what are you thinking?

6. klimenkov

You can factor this only in case if you have real roots. They will be if the discriminant of your equation is bigger that zero.

7. alexwantstolearn

the b^2-4ac > 0 means there are two distinct real roots

8. alexwantstolearn

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9. thisisarri

oh, soo than my guess was wrong? @klimenkov @alexwantstolearn

10. alexwantstolearn

its is the middle on you are correct that part will tell you how many x intercepts there are

11. alexwantstolearn

i will provide an example

12. alexwantstolearn

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13. thisisarri

ohh, hah cool! so i am right!

14. thisisarri

okay, so what about the second part?

15. alexwantstolearn

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16. alexwantstolearn

17. thisisarri

what?

18. alexwantstolearn

when you said the second part you want to know how that applies to that equation correct

19. thisisarri

noo, i mean this: Use the part of the quadratic formula that you chose above and find its value given the following quadratic equation: 2x2 + 7x + 3 = 0

20. alexwantstolearn

sorry i find it really hard to read when its not an image

21. alexwantstolearn

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22. alexwantstolearn

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23. thisisarri

sooo, ahah what is this?

24. alexwantstolearn

since its positive it means it has real roots

25. alexwantstolearn

sorry what part don't understand and i will try and explain it more clearly

26. thisisarri

like, there are so many numbers i dont know which one is the answer. so look at the b part that i typed a few minutes ago and tell me what i should put in it

27. alexwantstolearn

the answer too b is 25

28. alexwantstolearn

do you understand why that part of the quadratic equation is essential

29. alexwantstolearn

30. alexwantstolearn

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31. alexwantstolearn

are you happy with the answer i have shown the answer to a and b

32. alexwantstolearn

also i have explained why b^2-4ac is needed and gave an example of its use. I also calculated b for you and showed you what the value of a, b and c

33. thisisarri

yes, thank you soo much!!!

34. thisisarri

@alexwantstolearn