Mastery: Reasoning and Problem-Solving
- Draw an acute angle, estimate its size. Write your estimate. Then measure it. How close were you?
Repeat this for an obtuse angle.
- Draw a pentagon with two right angles and two obtuse angles. Can you draw a pentagon with three acute angles?
- True or False?
A quadrilateral could have two reflex angles.
- Draw a straight line divided into three acute angles. Measure two of the angles and calculate the third. Then measure it to check.
- Draw four angles around one point, where one of them measures 90°. Measure and label the other three angles.
- The three angles inside a regular (equilateral) triangle are all 60°, so add to 180°. The four angles inside a regular quadrilateral (square) are all 90°, so add to 360°.
- The sum of the five angles inside a regular pentagon follows a pattern begun by the triangle and square. Can you calculate how big each one is?
This unit has no separate problem-solving activities for Y6.
Y5 Use Day 1’s investigative Group Activity
Y6 Use the Day 1-2 investigative Group Activity