Solution :
According to Boyle's law, $$PV=$$ constant
$$\eqalign{
& \therefore \,\,{\text{log}}\,P + {\text{log}}\,V = {\text{constant}} \cr
& \,{\text{log}}\,P = - {\text{log}}\,V + {\text{constant}} \cr} $$
Hence, the plot of $${\text{log}}\,P\,\,{\text{vs}}\,\,{\text{log}}\,V$$ is straight line with negative slope.