one side of a rectangle is 3 cm shorter than the other side . if we increase the length of each side by 1 cm , then the area of the rectangle will increase by 16 cm 2 . find the lengths of all sides .
"let x be the length of the longer side x > 3 , then the other side ' s length is x − 3 cm . then the area is s 1 = x ( x - 3 ) cm 2 . after we increase the lengths of the sides they will become ( x + 1 ) and ( x − 3 + 1 ) = ( x − 2 ) cm long . hence the area of the new rectangle will be a 2 = ( x + 1 ) ⋅ ( x − 2 ) cm 2 , which is 16 cm 2 more than the first area . therefore a 1 + 16 = a 2 x ( x − 3 ) + 16 = ( x + 1 ) ( x − 2 ) x 2 − 3 x + 16 = x 2 + x − 2 x − 2 2 x = 18 x = 9 . so , the sides of the rectangle are 9 cm and ( 9 − 3 ) = 6 cm long . so answer is b ."
subtract(add(divide(16, 2), 1), 3)