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 × 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