First let us represent
x-width
x+3-length
Since it has a width and length, we can say it is a rectangle so the formula for the perimeter of it is 2(l+w)
p=2(l+w)
58=2(x+3+x)
58=(2x+3)2
58=4x+6
52=4x
x=13
the width is 13 and the length is 16
Subtract 4/7 on both sides to get b=-4/7-3. Then simplify.
28 could have just looked it up