https://binary2hex.com/rectangle-area.html?id=6

Area of a rectangle with a diagonal 123456 and side 1230 equal to 151843343.79

Rectangle area calculation method
Side a (or b): Diagonal d:

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

Solution:
S =
d2-a2
=
1230·1234562-12302
=
1230·15241383936-1512900
=
1230·15239871036
=
1230·123449.873
=
151843343.79

a: Area of a rectangle with a diagonal 123456 and side 1230 equal to 151843343.79