Answer:
Area of rectangle(A) is given by:
....[1]
where,
b is the base and h is the height of the rectangle.
As per the statement:
kyleigh put a large rectangular sticker on her notebook.
The height of the sticker measures 18 cm.
⇒ h = 18 cm
Since, the base is half as long as the height.
⇒
cm
Substitute in [1] we have;

Therefore, 162 square cm is the area of the notebook does the sticker cover.