What is a segment I've been stuck on this question i am grade 7 and new to geometry

im not sure f the correct definition but this is how you would work a question out

The Area of a Segment is the area of a sector minus the triangular piece

There is a lengthy reason, but the result is a slight modification of the Sector formula:

Area of Segment = θ - sin (θ) 2 * r2 (when θ is in radians)

Area of Segment = (θ 360 * π - sin (θ) 2) * r2 (when θ is in degrees)