Respuesta :
A = WL
A = 340
W = L - 3
340 = (L-3)(L)
340 = L^2 - 3L
L^2 - 3L - 340 = 0
L = 20
W = l - 3
W = 20 - 3
W = 17
so the length is 20 inches and the width is 17 inches
A = 340
W = L - 3
340 = (L-3)(L)
340 = L^2 - 3L
L^2 - 3L - 340 = 0
L = 20
W = l - 3
W = 20 - 3
W = 17
so the length is 20 inches and the width is 17 inches
Answer:
The length and width of the rectangle are 20 inches and 17 inches .
Step-by-step explanation:
Formula
Area of a rectangle = Length × Breadth
As given
The width of a rectangle is 3 inches less than its length. The area of the rectangle is 340 square inches.
Let us assume that the length is denoted by l.
Thus
Breadth = l - 3
Put in the above formula
340 = l × (l - 3)
340 = l² - 3l
l² - 3l - 340 = 0
l² - 20l + 17l - 340 = 0
l(l-20) + 17 (l-20) = 0
(l - 20) ( l+ 17) = 0
l = 20
l = -17 (This valueof length is neglected because length cannot be negative.)
As l = 20 inches
Breadth = 20 - 3
= 17 inches
Therefore the length and width of the rectangle are 20 inches and 17 inches .