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The area of a rectangle is 21 m squared, and the length of the rectangle is 1 m less than twice the width. Find the dimensions of the rectangle. Help?

User Beverly
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1 Answer

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This should be right because I checked it afterwards
Width=W
Length=2W-1
The equation is as follows
W(2W-1)=21

2W^(2)-W=21
Subtract 21 from each side

2W^(2)-W-21
Group them/put them in parentheses..can't think of the right word right now
(2W-7)(W+3)
-7=I7I
You only do this for the first parenthese, 7÷2W=3.5
W=3.5
If W=3.5 then 2W-1⇒2×3.5-1⇒7-1⇒6
Length=6
If W=3.5 and L=6, then W(2W-1)=21
3.5(2×3.5-1)=21
Solve in parentheses first
3.5(7-1)=21
3.5(6)=21
3.5×6=21
The width is 3.5
The length is 6

User Morxa
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