Which explanation justifies how the area of a sector of a circle is derived? - determine how many triangles can fit into a circle. divide 360° by the number of triangles. multiply the quotient by the area of the circle . - calculate the area of the circle. then, determine the central angle of the sector and divide this angle by 360° to get a fraction. multiply the area of the circle by this fraction. - partition the circle into unit squares. determine the area of the sector and multiply the area by the degree of the circle. - determine the degree of the sector. divide by 180° and then multiply it by the area of the triangle the sector is in.