The graph of y=|x| looks like a "V" with the point at the origin (0,0). The absolute value is always positive and it is equal to the magnitude of x. It always has a positive value.
"Vertically stretched" means multiplied by 3. If you stretch something that is 1 foot long to become 3 times its length, it is 3 units long. And an object initially 2 units long becomes 6 unites long.
So, the new function is also in the shape of a "V" but somewhat skinnier (this is really fun to do to someone's photo using Photoshop). Three times is far worse than Barbie, however. Also note: they used to use ropes to tie people to wheels to "stretch" them.
As a kid, my brother (always 3 years older, so you could say, HisAge=MyAge+3) came home from school and wanted to play "Stretch." We took a big knife, stood 3 feet apart facing each other, and threw the knife into the ground -- you're out if you hit a foot and it didn't count if it didn't stick or it was more than a knife's length away; but otherwise he must "stretch" to move his foot to the position of the knife. When you can't "stretch" (thus, fall down), you lose. Oh -- and you both lose when mom can't find her big cutting knife and comes to check on you (DON'T TRY THIS AT HOME!)