California Assessment of Student Performance and Progress (CAASPP) Math Practice Exam

Which statement about angles is true?

1. A right angle is less than 90 degrees

2. An obtuse angle measures exactly 180 degrees

3. A right angle can be marked with a small square

4. An acute angle cannot exceed 90 degrees

The correct answer is: A right angle can be marked with a small square

The statement regarding a right angle being marked with a small square is accurate. In geometry, a right angle is defined as an angle that measures exactly 90 degrees. To visually represent this, a small square is commonly used in diagrams to indicate that the angle formed is a right angle, confirming that the two lines or segments meet at a perfect 90-degree angle. The understanding of angle measurement helps clarify why other options are not true. For instance, a right angle cannot be less than 90 degrees, as it is defined solely at that measurement. Similarly, obtuse angles, by definition, measure more than 90 degrees and less than 180 degrees, making the statement that an obtuse angle measures exactly 180 degrees incorrect. The definition of acute angles stipulates that they are less than 90 degrees, thus they indeed cannot exceed that measurement, but this does not validate the other statements. Therefore, the marking of a right angle with a square effectively illustrates its unique measurement property.