The length of a rectangle is 2 inches more than a number. The width is 1 inch less than twice the same number. If the area of the rectangle is 42 in2 find the dimensions of the rectangle

Respuesta :

Answer:

length: 6 inches

width: 7 inches

Step-by-step explanation:

Let n represent the number. Then the length is (n+2) and the width is (2n-1). The product of these dimensions is the area:

42 = (n+2)(2n -1) = 2n^2 +3n -2

2n^2 +3n -44 = 0 . . . . subtract 42

(n -4)(2n +11) = 0 . . . . . factor

n = 4 . . . . . . . . we aren't interested in the negative solution

Length = 4+2 = 6 . . . inches

Width = 2·4 -1 = 7 . . . inches