GRE Math Review 3 GEOMETRY

A common way to indicate that an angle is a right angle is to draw a small square at the vertex of the angle, as shown in Geometry Figure 4 below, where P O N is a right angle. Geometry Figure 4. An angle with measure less than 90º is called an acute angle, and an angle with measure between 90º and 180º is called an obtuse angle. ................
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