A rectangle stained glass window is 2 feet by 4 feet. A clear glass border is constructed around the stained glass window. The width of the border is equal and was made out of 7 square feet of clear glass. What is the width of the border.
2 x 4 window with 7 ft^2 border
border is 2 sides x 4 tall x w on the long sides
and on the top/bottom will be 2 sides x (2 ft + 2w) * w
added together = 7 (w will be in feet)
2 x 4 x w + 2 x (2 + 2w)w = 7
8w + 2 (2w+2w^2) =7
8w + 4w + 4w^2 = 7
4w^2 + 12w - 7 = 0 Use Quadratic FOrmula to find w = .5 or (-3.5) <-----throw out
w = .5 ft = 6 inches width of border
.....a little clarification ( I did this in my mind....but you may not think like me! At least I hope you don't ! )
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