Question 392187
Originally a rectangle was twice as long as its wide. When 5 m was subtracted from its length and 3 m was subtracted from its width, the new rectangle had an area of 55m. Find the dimensions of the NEW rectangle. ( not the old dimensions ) 
Please show work clearly for me to understand.
Thanks :D 
This is what I tried:
Let length = 2x-5
Let width = x-3
( 2x-5) ( x- 3 ) = 55
2x^-6x-5x+15=55
2x^-11x+15=55
2x^-11x-40=0
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2x^2-16x+5x-40 = 0
2x(x-8)+5(x-8) = 0
(x-8)(2x+5) = 0
Positive solution:
x = 8
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Use that to answer the original question.
Also, you know you can always use the Quadratic
Formula to solve quadratic equations.
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Cheers,
Stan H.
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