# Math Help - graphing question

1. ## graphing question

for the longest while i've been working on this question
can any 1 help me out here

Code:

f(x) = 3^(x + 1) and g(x) = 3-x + 3 .
Find the point of intersection of the graphs of f and g by solving f(x) = g(x).

2. $3^{x+1} = 3-x+3$

Is that it? g(x) seems strange...

3. sorry this is what the question said
Code:
3^{x+1} = 3^{-x+3}

4. $3^{x+1} = 3^{3-x}$

Insert log on both sides:

$\log 3^{x+1} = \log 3^{3-x}$

$(x+1)\log 3 = (3-x)\log 3$

$(x+1) = (3-x)$

Can you finish now?

5. so am i solving for x

then what

6. You don't need to use quadratic...

7. so how am i going to get the points

8. You solve for x...

$x+1 = 3-x$

9. 3-x -x -1=0

-2x +2 = 0
x = -1

is it this
what do i do after

10. Since you are looking for the point of intersection, you are looking for a coordinate.

You already have the x coordinate, what can you do it this and the two equations:

$f(x) =3^{x+1}$

$g(x) = 3^{x-3}$

11. so i solved the equation above and got -1
so am i going to substitute it in fx and gx
and solve

12. Yes

Substituting in either f(x) or g(x) should be enough though.

13. i guess i have to substitute for both

bcuz they said for f and g

for f i got (-1,1)
any suggestions

14. Well... actually you didn't solve for x properly... I thought that you were doing the calculations well, but a small mistake crept in:

-2x +2 = 0

-2x = -2
x = 1

15. cud u jus verify this for me
0 = 3-1-2x
0 = 2-2x
-2= -2x
x=1

f(x) = 3^(x+1)

f(x) = 3^ (1+1)
f(x)= 9

g(x) = 3^(-1+3)

g(x) = 3^(2)
g(x) = 9

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