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A rectangle is a geometric shape that has four right angles (90°) and opposite sides are equal and parallel.

Rectangle area formula
where a and b are sides.

A rectangle is a geometric shape that has four right angles (90°) and opposite sides are equal and parallel.

Rectangle area formula
or
where a or b - side, P is the perimeter.

A rectangle is a geometric shape that has four right angles (90°) and opposite sides are equal and parallel.

Rectangle area formula
or
where d is diagonal, a or b - side.

A rectangle is a geometric shape that has four right angles (90°) and opposite sides are equal and parallel.

Rectangle area formula
where d is diagonal, α° is the angle between them in degrees.

A rectangle is a geometric shape that has four right angles (90°) and opposite sides are equal and parallel.

Rectangle area formula
or
where R is the radius of the circumscribed circle, a or b - side.

Rectangle area formula
or
where R is the radius of the circumscribed circle, a or b - side.

Solution: