I hate rounding.
Let's call the diagonal x. It's the hypotenuse of the right triangle whose legs are the rectangle sides.
According to the problem we have a length x-4 and a width x-5 and an area
82 = (x-4)(x-5)
82 = x^2 - 9x + 20
0 = x^2 - 9x - 62
That one doesn't seem to factor so we go to the quadratic formula

Only the positive value makes any sense for this problem, so we conclude

That's the exact answer. Did I mention I hate rounding? That's about
x = 13.6 meters
Answer: 13.6
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It's not clear to me this problem is consistent. By the Pythagorean Theorem the diagonal satisfies

which works out to

That's not consistent with the first answer; this problem really has no solution. Tell your teacher to get better material.
Answer:
Third option
O 100 cm
1m
Step-by-step explanation:

Answer: the length is 87 feet
The width is 40 feet
Step-by-step explanation:
Let L represent the length of the playing field.
Let W represent the width of the playing field.
The playing field is rectangular. The formula for determining the perimeter of a rectangle is expressed as
Perimeter = 2(L + W)
The perimeter of a playing field for a certain sport is 254 ft. This means that
254 = 2(L + W)
L + W = 254/2
L + W = 127 - - - - - - - - - - - -1
The length is 47 ft longer than the width. This means that
L = W + 47
Substituting L = W + 47 into equation 1, it becomes
W + 47 + W = 127
2W + 47 = 127
2W = 127 - 47 = 80
W = 80/2 = 40
L = W + 47 = 40 + 47
L = 87

The given statement can be represented as :
where, the number is assumed to be " b "
therefore, the correct choice is B. 2b³ - b