The perimeter of a rectangle is 42 inches. If the width of the rectangle is 6 inches, what is the length?

The formula for the perimeter of a rectangle is given by P = 2L + 2W, where L is the length and W is the width.

Given that the width of the rectangle is 6 inches, we can plug this into the formula:
42 inches = 2L + 2(6 inches)

This simplifies to:
42 inches = 2L + 12 inches

Subtracting 12 inches from both sides gives:
30 inches = 2L

Dividing both sides by 2 gives:
15 inches = L

Therefore, the length of the rectangle is 15 inches.