I’m not expecting you to eyeball it but you will have to do some basic math 🙂
To find the length of the original event (what Vegas calls a clip), double click it and look down in the box at the (as I recall) bottom right of the screen. I’m not at my computer right now so this is from memory. That box will show you the event length.
For this example we’ll assume a framerate of 60i and an even numbered length.
Let’s say the first event is 06:20 (seconds and frames) long and you want to slow it down by /2. The new length will be 6:20 x 2 = 12:40 = 15:10.
Enter this length into the same box. The highlighted event will now be this new length.
Ctrl+drag it out to the new length.
It works the same if you were to shorten it. All you have to is some simple math, enter that value into the box and adjust accordingly.
I sure hope that makes sense to you 🙂