The best way to install Inkscape is by using the Ubuntu Sotware Center.
Simply open Software Center and search on elisa
Click on Elisa and follow the prompts to install the Elisa.
To install Elisa via PPA open terminal via menu or via keys CLT+ALT+T.
udo add-apt-repository ppa:guijemont/ppa
This will enable the PPA for Elisa in your system.
Next you have to update the system before install. With the command below you will update the repositories.
sudo apt update
After update you can install elisa via the command below:
sudo apt install elisa
Once installed you can start the application from your Desktop Menu.