Answer: wheres the picture
Step-by-step explanation:
Graph the absolute value by using the vertex and a few selected points
Point One: X= -1, Y= -8
Point Two: X= 0, Y= -2
Point Three: X= 1, Y= 4
Point Four: X= 2, Y= -2
Point Five: X= 3, Y= -8
The graph should look something like a mountain or an upside down V
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.
You multiply pi times 3m which equals 9.42