# Math Help - Solving exponential equation using a... graph?

1. ## Solving exponential equation using a... graph?

What am I suppose to look for on the graph, in order to solve this?
Sorry if this seems obvious.
Use a graph to solve the equation 2^-x - 6

2. Originally Posted by Såxon
What am I suppose to look for on the graph, in order to solve this?
Sorry if this seems obvious.
Use a graph to solve the equation 2^-x - 6
is the equation supposed to be

$2^{-x} = 6$

???

3. maybe you mean 2^-x -6=0??

4. oh wow, sorry yes it is (2^-x) - 6 = 0...

5. Originally Posted by Såxon
oh wow, sorry yes it is (2^-x) - 6 = 0...
you could use a graph on a calculator and calculate the root.

or ...

$2^{-x} = 6$

$\ln(2^{-x}) = \ln(6)$

$-x \cdot \ln(2) = \ln(6)$

$x = -\frac{\ln(6)}{\ln(2)}$