Examples of transform: scale(x,y)

See the code

Scale Values: 1 = normal, < 1 = shrink, > 1 = grow, 0 = disappear
Negative values will flip the element along the indicated axes.
scaleX(x) and scaleY(y) methods are also available.

scale(1,1)
No change in size
scale(1,2)
Double in height (vertical), same width
scale(2,1)
Double in width (horizontally), same height
scale(1.5,1.5)
Increase size horizontally and vertically
scale(1.5)
Increase overall size (same as above)
scale(0.5)
Shrink to half-size
scale(-1,1)
Flip on x-axis (mirror image)
scale(1,-1)
Flip on y-axis (invert image)
scale(-1)
Flip on both axes

Source: Snowman Image