Who knows how to do this

Answer:
Step-by-step explanation:
Given,
As we know that the all sides of the square are equal.
Length of a square paper = 12 cm
Area of square = ?
Now, let's find the area of square
[tex] = {l}^{2} [/tex]
plugging the value of length,
[tex] {(12)}^{2} [/tex]
Evaluate the power
[tex] = 144[/tex] square cm
Hope this helps...
Best regards!!