Measuring angles (age 9+)
Recognise angle measure as additive; find unknown angles by adding or subtracting on a diagram using equations with a symbol for the unknown
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If two angles sit next to each other on a straight line and one is 65°, can your child work out the other angle — knowing that angles on a straight line always add up to 180°?
Recognise angle measure as additive; find unknown angles by adding or subtracting on a diagram using equations with a symbol for the unknown
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Check understanding
- Two angles on a straight line are 65° and x°; find x = 115°
- An angle is decomposed into 35° and 40°; state the whole angle is 75°
- Solve: angles at a point are 120°, 90°, and x°; find x = 150°
“If two angles sit next to each other on a straight line and one is 65°, can your child work out the other angle — knowing that angles on a straight line always add up to 180°?”
Curriculum record
- Type
- Procedural
- Subject
- Mathematics
- Domain
- Geometry
- Age range
- Ages 9–10