Question

Can someone please help me with this? Its finding functions and graphing data: http://nlvm.usu.edu/en/nav/frames_asid_328_g_4_t_2.html?open=activities&from=category_g_4_t_2.html

Answer 1

Ok so if you look at the two points already plotted they are (1,2) and (2,4) to get the next one look at the third shape count the number of triangles and then count the number of edges on the outside, and so on for the rest

Answer 2

I don't understand how to find out the function.

Answer 3

Thats pretty much all i need help on is the function.

Answer 4

oh ok so it is clearly a straight line so we use y=mx+b
take and two point, find the slope, then plug in one point to find the y-intercept

Answer 5

*any two point

Answer 6

Oh okay .

Answer 7

I dont think that it is a straight line because the table is like this
X |1 | 2 | 3 | 4 |
Y |1 | 3 | 9 | 27 |

Answer 8

Maybe I looked at the wrong one, so find a pattern in the y values how are they increasing as x increases?

Answer 9

Well it starts as one then it increases by multiples of three but skips 6 . Like 1 *3 = 3
3*3=9 9*3= 27

Answer 10

ok think of it like this starting from x = 2 : you have 3 than x = 3: 3*3, than x = 4 : 3*3*3.... and so on

Answer 11

So it doesnt have a constant function ?

Answer 12

As x changes so does y, so it is a function y(x)= ....

Answer 13

Ohhhhhhhhhh .

Answer 14

Figure it out?

Answer 15

No. lol.

Answer 16

Haha ok lets say the values we had were
x= 1, y = 2
x= 2, y = 2*2
x = 3, y = 2*2*2
x = 4, y = 2*2*2*2
what would you say the equation was?

Answer 17

y=2^x?

Answer 18

yup so your numbers are similar but with 3 and slightly shifted we have
x=1, y=1
x=2, y= 3
x=3, y=3*3
x=4, y=3*3*3
and so on

Answer 19

ignore x=1 and look at the rest

Answer 20

Oh okay so its y=x^3? or y=3^x?

Answer 21

y= 3^x is close but if x = 2 we get 9, x= 3 y = 27

Answer 22

Im so confused lol

Answer 23

ok just look at x=2
if we have y=3^x
where x=2, y=3^2, is 9 but we want 3
3^1=3
so what do we do to our 2 to get the right answer

Answer 24

Um i have no idean. .-. sorry

Answer 25

idea*

Answer 26

if you have 2 but you want a 1 what do you do to the 2?
simple math don't think about it too much

Answer 27

divide it by 2

Answer 28

right?

Answer 29

well thats one way not the way we want since it has to work for the rest
looking at the others we have the same problem we have 3 when we want 2, 4 when we want 3

Answer 30

um subtract one?

Answer 31

yes thats what we want

Answer 32

ok so back to 3^x
we need to do that to our x

Answer 33

okay so its 3^x-1?

Answer 34

yes! sorry its was hard to explain without just giving you the answer

Answer 35

Haha , thank you! Sorry i was so hard to teach :P

Answer 36

No problem