A shape is drawn on a centimetre grid. Write down the order of rotational symmetry of the shape.

Answer

The shape drawn on the centimetre grid is an isosceles triangle. To find the order of rotational symmetry, we need to determine how many times the shape looks exactly the same as its original position when rotated 360 degrees around its center point. Let's consider the properties of an isosceles triangle. An isosceles triangle has at least two sides of equal length and two equal angles. This specific triangle has a base of 2 units and a height of 4 units. It does not have all sides and all angles equal, which would make it an equilateral triangle. When we rotate any shape, it will always look the same after a full 360-degree rotation. This means every shape has at least an order of rotational symmetry of 1. If a shape has an order of rotational symmetry greater than 1, it means it can be rotated by less than 360 degrees and map onto itself. For an isosceles triangle that is not equilateral: 1. If we rotate it by 90 degrees, it will not look the same. 2. If we rotate it by 180 degrees, it will not look the same (the apex will point downwards, and the base will be at the top). 3. If we rotate it by 270 degrees, it will not look the same. 4. Only when we rotate it by 360 degrees does it return to its original orientation. Therefore, an isosceles triangle (unless it's also equilateral) has an order of rotational symmetry of 1. It only maps onto itself once during a full 360-degree rotation. Final Answer: 1