## anonymous one year ago y=x2-14x+44 find the domain and range, and the vertex of the following parabola. Show all work? Help?

1. anonymous

@laughoutloud

2. laughoutloud

hey do want to know how to do it or just the answer either way doesn't matter to me

3. anonymous

Well, everytime I try to solve the vertex my teacher keeps saying its wrong. So I need help with that. Also with the whole domain and range thing.

4. iGreen

@laughoutloud By the looks of his username, I think he wants to learn how to do it instead of just getting an answer.

5. anonymous

Yeah, I'd love to learn how to do it XD

6. laughoutloud

ok, to find the vertex you need to use the formula $\frac{ -b }{ 2a }$

7. anonymous

Alright. So do I plug the x^2 into the 2a or the -b?

8. laughoutloud

9. anonymous

and the -14 into the -b?

10. laughoutloud

you plug in $\frac{ 14 }{ 2 }$

11. anonymous

OK.

12. anonymous

That'd make X a 7?

13. laughoutloud

yes so x = 7 now you have to find the y value.

14. laughoutloud

What do you think you have to do?

15. anonymous

Alright, so I just plug 7 into all the X values

16. laughoutloud

yes

17. anonymous

Okay... Lemme solve it real quick

18. anonymous

y=(7)^2 - 14(7) + 44 y = 49 - 98 + 44 y = -49 + 44 y = -5 Is this correct?

19. laughoutloud

yes, I got the same

20. laughoutloud

so the vertex is?

21. anonymous

So, for the vertex it's (7, -5) right?

22. laughoutloud

yes

23. anonymous

Alright, how do we find the domain / range?

24. laughoutloud

the domain is going to be all of the x-values when this is graphed do you reach all of the x's eventually its kinda hard to explain

25. laughoutloud

That probably doesn't make sense

26. anonymous

Yeah... That's where I'm confused.

27. laughoutloud

Ok domain is all real

28. anonymous

Okay, sorry to trouble you more about the question... But sense I do all this stuff online and I'm just reading the stuff... How might I find the real numbers to explain to a teacher?

29. laughoutloud

sorry I'm not very good at explaining @carolinar7

30. anonymous

Alright, so.... Can you tell me how you got to your answer perhaps? @laughoutloud?

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