The area of the first rectangle would be 18cm² and the area of the second rectangle would be 12cm².
To calculate the area of a rectangle we must apply the following mathematical formula:
According to the above, to calculate the area of the rectangles we must multiply the length of the side by the base as shown below. We must also take into account the table that will give us the value of X that we do not know:
Finally, to know how much the area of both rectangles adds up, we add both values:
12cm² + 18cm² = 30cm²
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