anonymous one year ago I. Given the following polynomial: II. Use the quadratic formula to solve the following:

1. anonymous

help me i dont kno mathat all

2. Nnesha

what's the equation ?

3. Nnesha

post ur question here :=)

4. Nnesha

Given the following polynomial: ???

5. anonymous

look at the attachment

6. Nnesha

i didn't find the equation can you please post it here ?

7. anonymous

how do i do that?

8. Nnesha

like type in the equation toool ?

9. Nnesha

take a screenshot ?

10. anonymous

 The value of the discriminant is 169.  There are 2 real roots.  There are 2 irrational roots.  The graph intersects the y-axis twice.  The parabola is directed upward.  The axis of symmetry is located at  The vertex is located at:  The roots are:  The graph intersects the y axis at (0, -15).  The graph intersects the x-axis at (-5, 0) and (1.5, 0) II. Use the quadratic formula to solve the following:

11. Nnesha

what's the polynomial ?

12. Nnesha

there should be an equation Ax^2+Bx+C like this

13. anonymous

2xexponet2+7x-15=0

14. Nnesha

$\huge\rm 2x^2+7x-15=0$ quadratic equation ax^2+bx+c quadratic equation where a=leading coefficient b=middle term c-constant term so what is a b and c in that equation ? $\huge\rm x=\frac{ -b \pm \sqrt{b^2-4ac} }{ 2a }$quadratic formula

15. Nnesha

$$\huge\color{reD}{\rm b^2-4ac}$$ Discriminant you can use this to find if the equation is factorable or not if  b^2-4ac > 0 then there are 2 real zeros if  b^2-4ac = 0 then there is one real root if  b^2-4ac < 0 then you will get two complex roots (no -x-intercept)

16. Nnesha

substitute a b and c value into b^2 -4ac do you get 169 ?

17. anonymous

idk how to domath miss

18. Nnesha

Ax^2+Bx+C standard form equation of parabola where a = leading coefficient b= middle term c=constant term now look at this equation 2x^2+7x-15 what is a b and c ?

19. anonymous

2x is a 7x is b

20. Nnesha

just the coefficient 2 =a 7=b c = ?

21. anonymous

15

22. Nnesha

-15

23. Nnesha

alright $\huge\rm b^2-4ac$ substitute b a and c values then sovle

24. Nnesha

solve*

25. anonymous

how

26. Nnesha

just replace b with 7 a with 2 c with -15

27. Nnesha

here is how i would replace b with 7...... $\rm (7)^2-4ac$ ur turn replace a with 2 and c with -15

28. anonymous

49-8-15 that what i got

29. Nnesha

it's 4 times a times c it would bbe $49 -8(-15)$ now solve

30. Nnesha

hello ?

31. anonymous

idk

32. Nnesha

that's not an answer you don't know or you don't want to do it ? you can use calculator just put 49-8(-15) into the calculator that's it

33. anonymous

56

34. Nnesha

that's not correct!

35. Nnesha

49 -8(-15) first multiply -8 times -15 then add 49

36. anonymous

thats what i got both times

37. Nnesha

-8 times -15 = ?

38. anonymous

1065

39. Nnesha

did you really get that ?

40. anonymous

yea

41. Nnesha

guess what ... try again make sure you typed -8 times -15 into the calculator

42. anonymous

120

43. Nnesha

yes right 49+120 = ? that would be discriminant

44. anonymous

169

45. Nnesha

yes right so first sentence is right ?  The value of the discriminant is 169