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Area of rectangle with perimeter 5 and side 5 equal to -12.5

Rectangle area calculation method
Side a (or b): Perimeter P:

Rectangle

A rectangle is a geometric shape that has four right angles (90°) and opposite sides are equal and parallel.
Rectangle area formula Rectangle area formula Through the perimeter and one of the sides or Rectangle area formula Through the perimeter and one of the sides where a or b - side, P is the perimeter.

Solution:
S =
P·a - 2·a2
2
=
5·5 - 2·52
2
=
25 - 50
2
=
-25
2
=
-12.5

a: Area of rectangle with perimeter 5 and side 5 equal to -12.5