9514 1404 393
Answer:
7 in
Explanation:
For width w in inches, the length is given as 2w+1. The area is the product of length and width, so we have ...
A = LW
105 = (2w +1)w
2w^2 +w -105 = 0
To factor this, we're looking for factors of -210 that have a difference of 1.
-210 = -1(210) = -2(105) = -3(70) = -5(42) = -6(35) = -7(30) = -10(21) = -14(15)
So, the factorization is ...
(2w +15)(w -7) = 0
Solutions are values of w that make the factors zero:
w = -15/2, +7 . . . . . negative dimensions are irrelevant
The width of the rectangle is 7 inches.