It looks like (and is) a rectangle. All angles will be 90 degrees.
a L
You went 360o in the same direction, so you end up with a circle.
The answer will depend on whether the rotation is clockwise or counterclockwise.
3 o'clock
Clockwise means turning to your right, counterclockwise is to the left.
(x,y)-> (-y,x)
what will the letter Y look like if it is turned 90 degrees to the left
Both will end up on the same place. Using a compass rose as an example: 270 clockwise will point to the west. 90 counterclockwise will also point west.
(-1, -4) rotated 90 degrees anticlockwise
It looks like (and is) a rectangle. All angles will be 90 degrees.
{1 0} {0 -1}
It is (-1, 6).
a L
A 90-degree angle looks like one corner of a square or a rectangle.
You went 360o in the same direction, so you end up with a circle.
yes