The perimeter of a rectangle, is all of the sides added up.
In a rectangle, there are two widths (right and left), and two lengths (up and down)
So:
Perimeter = 2 × width + 2 × length.
To get the equation we just substitute in the values that we are given:
length = (x)
width = (x - 4)
perimeter = 87
So just put these values into: perimeter = 2 × width + 2 × length:
87 = 2(x) + 2(x - 4)
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Answer:
The equation is: 87 = 2(x) + 2(x - 4)
(note: this can be simplified down like so:
87 = 2x + 2x - 8
87 = 4x - 8
95 = 4x
23.75 = x
)
