a rectangular room has the rectangular shaped rug shown as above figure such that the rug ’ s area is 140 square feet and its length is 4 feet longer than its width . if the uniform width between the rug and room is 4 feet , what is the area of the region uncovered by the rug ( shaded region ) , in square feet ?
"rug ' s area = 140 which is ( x ) x ( 4 + x ) = 140 so x = 10 rug maintains a uniform distance of 4 feet so room has dimension 10 + 8 and 14 + 8 i . e . 18 and 22 area of room 18 x 22 = 396 area covered is 140 so uncovered area is 396 - 140 = 256 ( answer e )"
subtract(multiply(add(subtract(divide(140, const_10), const_2), const_10), add(divide(140, const_10), subtract(divide(140, const_10), const_2))), 140)