Problem Analysis:
The worksheet asks us to identify different types of angles based on the provided diagrams and answer questions about their properties. Let's analyze each part step by step.
#### Diagrams:
-
A: The angle appears to be less than 90°.
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B: The angle is marked with a square, indicating it is exactly 90°.
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C: The angle appears to be greater than 180°.
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D: The angle appears to be greater than 90° but less than 180°.
#### Definitions of Angles:
1.
Right Angle: An angle that measures exactly 90°.
2.
Reflex Angle: An angle that measures more than 180° but less than 360°.
3.
Acute Angle: An angle that measures less than 90°.
4.
Obtuse Angle: An angle that measures more than 90° but less than 180°.
Solution:
#### Question 1: Which angle is a right angle?
- From the diagrams,
B is marked with a square, which indicates a right angle.
-
Answer: B
#### Question 2: Which angle is a reflex angle?
- A reflex angle is greater than 180°. In the diagrams,
C is the only angle that appears to be greater than 180°.
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Answer: C
#### Question 3: Which angle is an acute angle?
- An acute angle is less than 90°. In the diagrams,
A is the only angle that appears to be less than 90°.
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Answer: A
#### Question 4: Which angle is an obtuse angle?
- An obtuse angle is greater than 90° but less than 180°. In the diagrams,
D is the only angle that appears to fit this description.
-
Answer: D
#### Question 5: How many degrees are there in a right angle?
- By definition, a right angle measures exactly 90°.
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Answer: 90
Final Answers:
1.
B
2.
C
3.
A
4.
D
5.
90
Boxed Final Answer:
\[
\boxed{B, C, A, D, 90}
\]
Parent Tip: Review the logic above to help your child master the concept of reflex angle worksheet.
