To prove that segment AC is the angle bisector of the figure, we need to know the measure of the angles formed by segment AC, as well as the measure of the angles formed by the other two sides of the figure. If the measure of the angles formed by segment AC are exactly half of the measure of the angles formed by the other two sides of the figure, then we can prove that segment AC is the angle bisector of the figure. Additionally, if the figure is not to scale, we can use the Pythagorean Theorem to calculate the angles and sides of the figure, since the angles and sides of a right triangle can be calculated using the lengths of the sides.