Find the area of a parallelogram if a base and corresponding altitude have the indicated lengths.

Base x yards, altitude 3y feet.

We are asked to solve for the area of the parallelogram trapezoid where the formula is shown below:

Area = b * h where "b" are for the base and "h" for the height

We have the following given:

Base = x yards

Altitude = 3y feet

We know that 1 yard = 3 feet, convert base into feet units.

Base = x yards * (3feet/1 yard)

Base = 3x feet

Solving for the area:

Area = (3x) * 3y

Area = 9xy

The answer is 9xy feet².