A = 900

The area of a parallelogram can be found by taking its base (b) and multiplying by the height (h). The base has the measure of 33 +12 = 45 cm. Now, you just need to find the height of the parallelogram. The height can be found by using the pythagorean theorem (

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So, when simplified the height of the parallelogram will be found from

The height is 20 cm. The base is 45 cm. 45 x 20 = 900.