You have determined that you have constructed an accurate copy of an angle because if you just draw a ray, and measure the angle of the original angle, use that same compass setting and put it on the vertex of the ray that you just drew. Make an arc that intersects the ray. At that intersection point that you just made, draw another arc with that same compass setting, through the other arc, making intersecting lines. At that final intersection point, that's where you draw your line through. Now you have constructed an accurate copy of an acute angle.
