## anonymous one year ago please check my answer asap? what is the vertex of g(x)=|x+9|+3? I ended up with (9,-3).

1. jim_thompson5910

it's incorrect

2. jim_thompson5910

hint: vertex of `y = a|x-h| + k` is `(h,k)`

3. anonymous

@jim_thompson5910, does that mean that it would be (9,3)??

4. jim_thompson5910

closer but no

5. jim_thompson5910

compare `|x+9|` with `|x-h|` try to get them to match up

6. anonymous

@jim_thompson5910 I think i understand, would it mean that it is (-3, 9)? Substituting -3 for x then adding -3 to 9 would equal 6, plus 3 would make it 9 again? Is that correct?

7. jim_thompson5910

|dw:1441945109736:dw|

8. anonymous

I don't understand

9. jim_thompson5910

|dw:1441945133297:dw|

10. jim_thompson5910

|dw:1441945159391:dw|

11. jim_thompson5910

the a and 1 match up, so a = 1 |dw:1441945188226:dw|

12. jim_thompson5910

x+9 is the same as x - (-9) |dw:1441945210699:dw|

13. jim_thompson5910

so h and -9 match up |dw:1441945235318:dw|

14. jim_thompson5910

and finally, k = 3 |dw:1441945276083:dw|

15. nincompoop

|dw:1441945095395:dw|

16. anonymous

Where did the one come from??

17. jim_thompson5910

@hxj9314 all that I did was compare the general form `y = a|x-h|+k` with the specific equation `y = |x+9|+3`

18. jim_thompson5910

think of it as `x = 1*x` since 1 times any number is that same number

19. anonymous

Hm. Thinking about it, if i plug in -9,3 to the equation it makes it y=|-9+9|+3, making the y add up to the coordinate since y=3?

20. jim_thompson5910

yeah if x = -9, then y = 3 so (-9,3) is the lowest point as you can see in the graph at the link https://www.desmos.com/calculator/1gelnvft97

21. jim_thompson5910

you can click on the lowest point to have the coordinates show up

22. anonymous

@jim_thompson5910 Thank you so much. You helped me understand it.

23. jim_thompson5910