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A rectangle has a perimeter of 42 feet. Its length, L, is three feet more than twice its width, W. Create a equation in terms of L and W based on the perimeter of the rectangle.

1 Answer

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Answer: (a) 42= 2(3w+3)

(b) L= 2w+3

(c) w=6

l=15

Explanation:

(a): Create an equation in terms of L and W based on the perimeter of the rectangle:

SInce p= 2 (l+w)

All you do is substitute perimeter in (42) for p , 2w+3 for length, and w for width:

42= 2(...+...)

Length is 2w+3 so it'll be:

42=2(2w+3+w)

you can just combine the terms in parenthesis to get

42= 2(3w+3)

(b) Create an equation that relates L and W based on length being 3 feet more than 2x the width:

L= 2w+3 (2 times the width) ( plus 3 more then it)

(c) Solve by find L and W using substitution:

Use your first equation:

42= 2(3w+3)

Solve it:

42= 6w+6

-6 to both to get:

36=6w

Divide by 6

You'll get width= 6

Now using this: L= 2w+3

Plug in 6 for w

L= 2(6)+3

L=15

So,

w=6

l=15

Hope this helps!!!

God bless!!!

User Broken Man
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