To find the area of the joined rectangle, you need to add the areas of both rectangles and subtract the area of the overlap.
The area of the first rectangle is:
6 cm x 4 cm = 24 cm²
The area of the second rectangle is:
7 cm x 3 cm = 21 cm²
The overlap occurs where the two rectangles join together, and it has an area equal to the product of the widths of the two rectangles:
4 cm x 3 cm = 12 cm²
To find the area of the joined rectangle, add the areas of both rectangles and subtract the overlap:
24 cm² + 21 cm² - 12 cm² = 33 cm²
Therefore, the area of the joined rectangle is 33 cm².