p=ln(a) agency accustomed log of a which is log abject e of a.

It is the backer p area e^p is a.

q=ln(e^-3x) is -3x

This is because we are demography the accustomed log abject e of e to the -3x power. So that is the backer q area e^q is e^-3x and from there we can see q=-3x.

It is not all-important to annular to 4 decimal places because we do not apperceive x.

8x-(2x+6)=30