Question 150815
If the length of a rectangular field is 8 feet more than double of its width. Find the dimensions of the field if its area is 540 square feet?
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Let w = width of field
2w+8  = length of field
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w(2w+8)= 540
2w^2+8w= 540
2w^2+8w-540 = 0
w^2+4w-270 = 0
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Since you can't factor you must use the quadratic equation.  Doing so yields:
w={14.55, -18.55}
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Only the positive answer would be correct.  Therefore:
w = 14.55 feet (width)
2w+8 = 37.1 feet (length)
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Below is the quadratic solution:
*[invoke quadratic "x", 1, 4, -270 ]