Question 1188666
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Mr.Ulep has a rectangular field with a length twice its width.
If 4 feet are taken from the length and 3 feet are taken from the width, 
the area of the field is 180 square feet.Find the area of the original field
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<pre>
Let x be the width; then the length is 2x.

The area equation is

    (2x-4)*(x-3) = 180,

or

    (x-2)*(x-3) = 90.

    x^2 - 5x + 6 = 90

    x^2 - 5x - 84 = 0

    (x+7)*(x-12) = 0


Of the two roots, x= -7  and  x= 12, only positive value x= 12 ft is the width.

Then the length is 2*12 = 24 ft.


<U>ANSWER</U>.  The area of the original rectangle is 12*24 = 288 ft^2.
</pre>

Solved.



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The method shown by @shin123 is formally correct, but essentially is anti-pedagogical.


Solve simple problems using simple methods.