Given the radius and height of the circle, how to find the area formula of the arch? The height and radius of the arch were 45cm and 125cm respectively

Given the radius and height of the circle, how to find the area formula of the arch? The height and radius of the arch were 45cm and 125cm respectively

Bow height is h = 45cm, radius is r = 125cm, chord length is L = 2 * (R ^ 2 - (R-H) ^ 2) ^ 0.5 = 2 * (125 ^ 2 - (125-45) ^ 2) ^ 0.5 = 2 * (125 ^ 2-80 ^ 2) ^ 0.5 = 2 * 96.047 = 192.094cm, center angle is a = 2 * arc sin ((L / 2) / R) = 2 * arc sin ((192.097 / 2) / 125) = 100.416 degree, bow area is s = pi * R ^ 2 * A /