Answer:
Length = 3
Width = 7
Explanation:
The perimeter is 20 feet
The area is 21 feet
Let x represent the length
Let y represent the width
20 = 2(x+y)
x+y= 20/2
x+y = 10.........equation 1
x × y= 21......equation 2
From equation 1
x= 10-y
Substitute 10-y for x in equation 2
(10-y)y= 21
10y - y^2 = 21
y^2 -10y + 21= 0
After factorization the result will be
(x-3)(y-7)
x-3= 0
x= 0+3
x= 3
y-7= 0
y= 0+7
y= 7
Hence the length is 3 and the width is 7