The perimeter of a rectangle is 48 cm. The length is 6 cm less than twice the width. Which system would model this situation, and what are the length and the width?
A.
2l + 2w = 48
l + 2w = 6
Solution: (9, 6)
B.
2l + 2w = 48
2l + w = –6
Solution: (–32, 56)
C.
l + w = 48
l – 2w = –6
Solution: (18, 6)
D.
2l + 2w = 48
l – 2w = –6
Solution: (14, 10)

Question

The perimeter of a rectangle is 48 cm. The length is 6 cm less than twice the width. Which system would model this situation, and what are the length and the width?
A.
2l + 2w = 48
l + 2w = 6
Solution: (9, 6)
B.
2l + 2w = 48
2l + w = –6
Solution: (–32, 56)
C.
l + w = 48
l – 2w = –6
Solution: (18, 6)
D.
2l + 2w = 48
l – 2w = –6
Solution: (14, 10)

anonymous · Answer

Well if $$l = 2w - 6$$ then we can eliminate A and B before doing much work because when re-arranging for length in both, I see that it's not equal to the right side of the above.

anonymous · Answer

And from the perimeter, we should have $$2l + 2w = 48$$

anonymous · Answer

So D, not C.