Question Number 144162 by bobhans last updated on 22/Jun/21
Commented by Rasheed.Sindhi last updated on 22/Jun/21
$$\mathcal{E}{xternal}\:{angle}\:{of}\:{pentagon} \\ $$$$\:\:\:\:\:\:=\mathrm{180}−\mathrm{108}=\mathrm{72} \\ $$$${x}+\mathrm{72}+\mathrm{72}=\mathrm{180} \\ $$$${x}=\mathrm{36} \\ $$