Let’s go step by step to name each angle correctly.
First, remember the definitions:
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Acute angle: Less than 90° (small and sharp)
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Right angle: Exactly 90° (looks like a corner of a square)
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Obtuse angle: More than 90° but less than 180° (wide and open)
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Straight angle: Exactly 180° (a straight line)
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Top Row – Identify the angles:
1. First angle: It has a small square in the corner → that means it’s a
right angle.
2. Second angle: Looks smaller than a right angle → that’s an
acute angle.
3. Third angle: It’s a straight line with arrows on both ends → that’s a
straight angle.
4. Fourth angle: Looks wider than a right angle but not straight → that’s an
obtuse angle.
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Bottom Row – Match the angle names using points A, B, C:
We need to look at which point is the vertex (the corner where the two lines meet). The middle letter in the angle name is always the vertex.
1. First diagram: Lines go from A to B and A to C → vertex is A → so the angle is ∠CAB or ∠BAC. Looking at the options, we have ∠CAB → match this one.
2. Second diagram: Lines go from B to A and B to C → vertex is B → so the angle is ∠ABC → match this one.
3. Third diagram: Lines go from C to B and C to A → vertex is C → so the angle is ∠BCA → match this one.
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Final Answer:
Top row (left to right):
Right, Acute, Straight, Obtuse
Bottom row (left to right):
∠CAB, ∠ABC, ∠BCA
Parent Tip: Review the logic above to help your child master the concept of angle worksheets.
