Elementary trouble with tied notes

I am having problems with tied notes. How can extend the duration of a note which is, a for example a minim tied to a crotchet without first using the scissors tool.
I use the scissors to seperate the tied notes and only then can I extend the duration of the note (say by another minim) followed by tieing the note combination back again
There must be a way of attaching a note of a given duration to a note that already contains ties without using the scissors tool.

shift-alt-right extends a note by the current grid spacing


Or just enter the additional duration as a separate note and tie them together with T.