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The width of a rectangular room is 7 metres shorter than it's length.If the perimeter must not exceed 38 metres, calculate the greatest length that the room can have.

User Hous
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2 Answers

1 vote

Answer: The perimeter is twice the length plus twice the width, or 2x+2y.

Therefore, 2x+2y = 38 as given.

Also, the length is 5 ft longer than the width so x = y + 5

Knowing these equations are true, you can solve.

Substitute for x: 2(y+5) + 2y = 38

Distribute: 2y + 10 + 2y = 38

Simplify: 4y + 10 = 38

Subtract 10: 4y=28

Divide by 4: y=7

x=y+5 = 12

The length is 12, which is 5 more than the width of 7. The perimeter is 2(12+7) = 2(19) = 38

Step-by-step explanation: I hope this answers your question. Have a nice day or night. :D

User DennisLi
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3.3k points
5 votes

Answer:

12

Explanation:

2a + 2b = 38

2(7) + 2b = 38

14 + 2b = 38

2b = 24

b = 12

User IMoeNya
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3.2k points