Answer:
9

Explanation:
The area of a parallelogram is equal to the base times the height.
The base is 3x and the height is also 3x so the area will equal
3x Ă— 3x
When you multiply variables you multiply the coefficients and add the exponents so when you multiply 3x and 3x you multiply 3 and 3 and the exponents 1 and 1 so you get 9