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Some common 2D shapes are: Triangles, Rectangles, Squares, Parallelograms, Trapeziums, Kites, Pentagons, Hexagons and Circles.
We will look at drawing some of these shapes using both grid paper and dotted paper.
We always use a ruler to draw any straight sides.
A right angled triangle has a base and a height which meet at 90 degrees.
It is easiest to draw
To draw a right-angled triangle, draw the base and the height first and then connect the two ends to form the third side.
In this example we have a right-angled triangle with a base and height both of 2 cm.
We draw the base by drawing 2 horizontal lines between the dots.
We then draw the height by connecting the dots with 2 lines. Each gap is 1 cm wide and so, 2 lines drawn end-to-end form a line that is 2 cm long.
We connect the two ends of the base and the height to form the third side.
Because we have measured the other two sides, we do not need to measure this third side, we just connect the two ends with a ruler.
In this example we have a right-angled triangle with a base of 1 cm and a height of 3 cm.
We start by drawing the base and height with a ruler.
The base is 1 cm long so we draw one horizontal line.
The height is 3 cm long so we draw 3 lines between the dots.
We now connect the two free ends of these lines to form the third side.
Here is an example of a right-angled triangle with a base of 4 cm and a height of 3 cm.
We draw the base and the height before connecting the two free ends.
Here is an example of drawing a right-angled triangle on grid paper.
It has a base of 5 cm and a height of 1 cm.
Each square on the grid paper is 1 cm apart.
Again, we draw the base and height first before joining the two ends.
We draw the base of 5 cm and then the vertical height of 1 cm.
We connect the ends with a ruler.
Isosceles triangles are symmetrical and have two sides the same length.
To draw an isosceles triangle draw the base length first. Measure the height from the middle of the base and mark a point. Connect this point to the two free ends of the base.
In this example we have an isosceles triangle with a base and height of 2 cm.
There is only one side that we know the length of and this is the base. It is 2 cm.
We draw this base first by connecting 2 lines with a ruler.
We then count the height upwards from the middle of this base.
The base is 2 cm long, so the middle is 1 cm inwards. We count up 2 cm for the height and mark a point.
We connect this point to each end of the base line.
In this example we have an isosceles triangle with a base of 4 cm and a height of 1 cm.
We know that the base is 4 cm and so we draw 4 lines with a ruler for this base.
We count upwards 1 cm from the middle of this base and mark a point.
We connect this point to each end of the base to complete the triangle.
In this example of an isosceles triangle, we can see that the base of the triangle is vertical. The triangle is on its side.
The only side length we know is the 6 cm side. We draw 6 lines upwards to draw this vertical base side.
The height is 5 cm and so, we count 5 centimetres from the middle of this base line and mark a point.
We connect this point to the two ends of the 6 cm line to complete the triangle.
In this example we have an isosceles triangle with a base of 4 cm and a height of 6 cm.
We will draw the triangle on grid paper this time.
The base is 4 cm and we count the height upwards from the middle of this line to mark the top of the triangle.
We now connect the top of the triangle to either side of the base line.
Rectangles have 4 sides and each side is the same length as the side opposite to it.
Here is an example of a rectangle with a length of 3 cm and a width of 1 cm.
We draw the length first with 3 horizontal lines.
From here we draw the width of 1 cm. We draw one line downwards.
Opposite sides on rectangles are the same length.
The base length is the same length as the top length. It is also 3 cm.
Finally we return to the beginning of the rectangle with a 1 cm line upwards.
In the example below we have a rectangle with a width of 2 cm and a length of 4 cm.
We draw 2 horizontal lines for the width and then 4 vertical lines for the length.
The opposite side lengths are then the same length.
Here is an example of drawing a rectangle on grid paper.
We have a rectangle with a base of 5 cm and a height of 3 cm.
We count 5 lines horizontally and 3 lines vertically.
We draw the opposite sides to compete the rectangle.
Here is an example of a square which has side lengths of 1 cm.
We draw a horizontal line 1 cm long and then a vertical line 1 cm down.
Again a square has all of its sides the same length. We go left 1 cm and finally we go up 1 cm.
Here is an example of drawing a square with side lengths of 2 cm.
Again all sides are the same length.
Here we have a square with side lengths of 5 cm.
We will draw this square using square grid paper.
We draw 5 lines horizontally and 5 lines vertically.
We draw the remaining lines 5 cm long to complete the square.
Now try our lesson on Naming 2D Shapes Using Sides and Corners where we learn how to find the names of some common 2D shapes.
We can rotate the shapes or look at their nets to find them.
Cylinder Triangular Prism Square-Based Pyramid
‘2D’ is short for 2-dimensional. 2-dimensional shapes are flat. 2D shapes only exist on flat surfaces, such as screens or paper.
‘3D’ is short for 3-dimensional. 3-dimensional shapes can be picked up and exist in real life.
Many common 3D shapes are made up of flat surfaces called faces. These faces are often some of the 2D shapes that we know.
To identify 2D Shapes on the surface of 3D shapes, rotate the 3D shape to look at each face or use a net of the shape to help you.
We can see a list of some common 2D shapes on the surfaces of 3D shapes on the poster below:
A cube is a 3D square. All of the edges on a cube are the same length and so, all of the faces are the same.
A cube is made up of 6 square faces. These 6 square faces are identical and are all at right angles to each other. Each square face is directly opposite another square face.
We can see the 6 faces of a cube by rotating it as shown or we can look at its net shown below.
This is one of the eleven different nets for a cube. Using this net, we can see that it is made up of 6 square faces.
A cylinder has 2 circular faces on the top and bottom. The side surface is a rectangle wrapped around the circles into a tubular shape.
A cylinder is a tube shaped 3d shape. It looks like a tin or can. It looks like a circle lifted upwards out of the paper it is drawn on.
We can see that the two circular faces are opposite to each other.
The side surface is curved, wrapped around the circular edges. Technically, faces must be flat and so this curved surface is not always counted as a face of a cylinder. We can see from the net below that this curved surface can be made from a rectangle wrapped around the side of the circles.
It is easiest to see the 2D shapes on the surfaces by looking at the net of the cylinder.
Here is the net of the cylinder with the faces shown.
A cuboid has 4 rectangular faces. Each face is identical in size to the face opposite to it.
A cuboid is a box-shaped 3D shape. It is a 3D rectangle.
A cuboid is a stretched cube. Therefore it has 6 faces just like a cube does.
We can see the 6 2D faces of a cuboid in the net below.
A cone has one flat circular face as its base and one curved surface that wraps around the circular face.
Again, faces are technically flat and so the only face on a cone is the circle on its base. However, sometimes curved surfaces are included.
We can see the net of the cone below, showing its circular 2D face.
A triangular prism has two triangular faces surrounded by 3 rectangular faces.
The front face is a triangle. The back face is a triangle that is identical to the front face.
We can see the net of a triangular prism below showing the 2D faces on its surface.
We have 3 rectangles and 2 triangles.
A square-based pyramid has one square face on its base and four triangular faces.
A square has four sides and so the square base has a triangle attached to each edge. We can see the square surrounded by four triangles shown on the square-based pyramid net below.
A triangular-based pyramid has four triangular faces, one on its base and three on its sides.
We can see the 2D shapes on the triangular-based pyramid below.
We can see the four 2D faces on the net of the triangular-based pyramid below.
Now try our lesson on Parallel Sides where we learn what parallel lines are and how to find them on shapes.
Return to video lesson on 2D Faces on the Surface of 3D Shapes
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Return to video lesson on 2D Faces on the Surface of 3D Shapes
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Return to video lesson on 2D Faces on the Surface of 3D Shapes
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Return to video lesson on 2D Faces on the Surface of 3D Shapes
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Return to video lesson on 2D Faces on the Surface of 3D Shapes
Share on Google Classroom:
Return to video lesson on 2D Faces on the Surface of 3D Shapes
Share on Google Classroom:
Return to video lesson on 2D Faces on the Surface of 3D Shapes
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