The step is necessary because it measures the radius of the inscribed circle
Step-by-step explanation:
In construction of an incenter, you first draw the angle bisector of at least two angles of the triangle, followed by constructing a perpendicular from the incenter to one side of the triangle to locate the exact radius then adjusting the compass point from the incenter and measure from the center to where the perpendicular crosses the side of the triangle.This last step measures the radius which will guide you in drawing the inscribed circle with correct measurements.
