SOLUTION: The length of a rectangle is twice it's width. If the width is reduced by 1cm and the length is reduced by 2cm, the area will be 15cm². The dimensions of the original rectangle.

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Question 1196616: The length of a rectangle is twice it's width. If the width is reduced by 1cm and the length is reduced by 2cm, the area will be 15cm². The dimensions of the original rectangle.
Found 3 solutions by ewatrrr, ikleyn, Alan3354:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

Hi
The length of a rectangle is twice it's width.
width w
length 2w
If the width is reduced by 1cm and the length is reduced by 2cm, 
the area will be 15cm².
A = length*width
(2w-2)(w-1) = 15cm²
Solve for w, rounding answer as instructed 
2w^2 -4w + 2 = 15

Wish You the Best in your Studies.


Answer by ikleyn(52790) About Me  (Show Source):
You can put this solution on YOUR website!
.

Let w be the width, in centimeters.

Then the length is 2w cm.


After changing the dimensions, they become (w-1) cm and (2w-2) cm.

The area equation is

    (w-1)*(2w-2) = 15.


Simplify and solve it MENTALLY

    2*(w-1)*(w-1) = 15

      (w-1)^2 = 15/2 = 7.5

       w-1 = sqrt%287.5%29

       w = 1+%2B+sqrt%287.5%29 = 3.74 cm.


ANSWER.  The dimensions of the original rectangle are  3.74 cm (the width)  and  2*3.74 = 7.48 cm (the length).

Solved.



Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
The length of a rectangle is twice it's [sic] width.
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it's = it is