The formula is F= 35e^-0.7p
make p the subject.
Thanks in advance I am not sure where to start.
You "undo" what has been done to p.
$\displaystyle 35e^{-0.7p}= F$
The last thing done on the left is "multiply by 35" so the first thing you do to solve for p is divide both sides by 35:
$\displaystyle 35e^{-0.7p}/35= e^{-0.7p}= \frac{F}{35}$
Now, we have an exponential function (e to a power). The reverse of that is the "natural logarithm". Take the logarithm of both sides:
$\displaystyle ln(e^{-0.7p})= -0.7p= ln(\frac{F}{35})$
Finally, p is multiplied by -0.7. Divide both sides by -0.7:
$\displaystyle -0.7p/(-0.7)= p= -\frac{ln(\frac{F}{35})}{0.7}$