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Step 1. Draw an arc that is centered at the vertex of the angle. This arc can have a radius of any length. However, it must intersect both sides of the angle. We will call these intersection points E and F This provides a point on each line that is an equal distance from the vertex of the angle.

Step 2. Draw two more arcs. The first arc must be centered on one of the two points E or F. It can have any length radius. The second arc must be centered on whichever point (E or F) you did NOT choose for the first arc. The radius for the second arc MUST be the same as the first arc. Make sure you make the arcs long enough so that these two arcs intersect in at least one point. We will call this intersection point X.

Step 3. Draw a line that contains both the vertex and X. Since the intersection points and the vertex all lie on the angle bisector, we know that the line which passes through these points must be the angle bisector

So ,measure of angle EDG=45 degree.Half of 90 degree.(answer)

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