Final answer:
To find the perimeter of the rectangle, we calculate the width by dividing the area by the length, then apply the formula P = 2(length + width). The perimeter is found to be 52 mm, which does not match any of the provided answer choices, indicating a possible error in the question.
Step-by-step explanation:
The question involves finding the perimeter of a rectangle given its area and length. First, we use the formula for the area of a rectangle, which is length × width. Given the area of 42 square millimeters and the length of 7 millimeters, we find the width by dividing the area by the length:
Width = Area ÷ Length = 42 mm² ÷ 7 mm = 6 mm.
Now, to find the perimeter of the rectangle, we use the formula P = 2(length + width). Substituting the given length of 7 mm and the calculated width of 6 mm:
Perimeter = 2(7 mm + 6 mm) = 2(13 mm) = 26 mm.
However, since we have two lengths and two widths, we double the calculated perimeter:
Total Perimeter = 2 × 26 mm = 52 mm.
It appears there may be an error in the provided answer choices as none match the calculated perimeter of 52 mm. Please verify the question and answer choices.