13 December 2021 Enlargement Lesson Objectives Developing students

13 December 2021 Enlargement Lesson Objectives: Developing students will be able to enlarge objects by a positive integer scale factor. Secure students will be able to enlarge objects by a positive fractional scale factor. Enlargement is a type of transformation. An enlargement changes the size of an object. The shape stays exactly the same but the size changes. We describe enlargements with a scale factor and a centre. Excelling students will be able to enlarge objects by a negative scale factor. Keywords Enlarge, size, scale factor, positive, negative, integer, fraction, centre, similar, congruent

13 December 2021 Enlargement Lesson Objectives: Developing students will be able to enlarge objects by a positive integer scale factor. Enlarge this object by scale factor 2. 2 squares Secure students will be able to enlarge objects by a positive fractional scale factor. Excelling students will be able to enlarge objects by a negative scale factor. Keywords Enlarge, size, scale factor, positive, negative, integer, fraction, centre, similar, congruent

Enlargement Lesson Objectives: Developing students will be able to enlarge objects by a positive integer scale factor. 13 December 2021 Enlarge this object by scale factor 2. 3 squares Secure students will be able to enlarge objects by a positive fractional scale factor. Excelling students will be able to enlarge objects by a negative scale factor. Keywords Enlarge, size, scale factor, positive, negative, integer, fraction, centre, similar, congruent

Enlargement Lesson Objectives: Developing students will be able to enlarge objects by a positive integer scale factor. 13 December 2021 Enlarge this object by scale factor 3. Secure students will be able to enlarge objects by a positive fractional scale factor. Excelling students will be able to enlarge objects by a negative scale factor. 2 squares Keywords Enlarge, size, scale factor, positive, negative, integer, fraction, centre, similar, congruent

Enlargement Lesson Objectives: Developing students will be able to enlarge objects by a positive integer scale factor. 13 December 2021 Enlarge this object by scale factor 3. Secure students will be able to enlarge objects by a positive fractional scale factor. Excelling students will be able to enlarge objects by a negative scale factor. 2 squares Keywords Enlarge, size, scale factor, positive, negative, integer, fraction, centre, similar, congruent

13 December 2021 Enlargement 10 Transform this triangle by the enlargement: 9 8 Identify the centre of enlargement. Scale factor 2 7 from centre (2, 1) 6 5 4 3 2 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Transform this triangle by the enlargement: 9 8 Scale factor 2 7 from centre (2, 1) 6 Calculate the distance from the centre to the shape. 5 4 3 2 One right, one up 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Transform this triangle by the enlargement: 9 8 Multiply this distance by the scale factor. Scale factor 2 7 from centre (2, 1) 6 This is the bottom left vertex of the new shape. 5 4 3 2 Two right, two up 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Transform this triangle by the enlargement: 9 8 Scale factor 2 7 from centre (2, 1) 6 5 4 Multiply every side length by the scale factor and draw in the new shape. 3 2 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Transform this triangle by the enlargement: 9 8 Identify the centre of enlargement. Scale factor ½ 7 from centre (0, 0) 6 5 4 3 2 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Transform this triangle by the enlargement: 9 8 Scale factor ½ 7 from centre (0, 0) 6 Calculate the distance from the centre to the shape. 5 4 3 2 1 0 0 Four right, two up 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Transform this triangle by the enlargement: 9 8 Multiply this distance by the scale factor. Scale factor ½ 7 from centre (0, 0) 6 This is the bottom left vertex of the new shape. 5 4 3 2 1 0 0 Two right, one up 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Transform this triangle by the enlargement: 9 8 Multiply every side length by the scale factor and draw in the new shape. Scale factor ½ 7 from centre (0, 0) 6 5 4 3 2 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement Describing Enlargements To describe an enlargement we need to know two things: The scale factor For example, s. f. 3 s. f. ½ s. f. -4 The centre of enlargement This is the fixed point from which the object is enlarged. We can find this by joining together two pairs of vertices on the object and the image.

13 December 2021 Enlargement 10 Describe the transformation that maps A onto B. 9 8 7 6 B 5 4 3 A 2 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Describe the transformation that maps A onto B. Scale factor 2 Compare the same side on the object and the image to find the scale factor. 9 8 7 6 B 5 4 3 A 2 0 s. f. 2 2 1 0 4 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Describe the transformation that maps A onto B. Scale factor 2 Identify a vertex on the object and its partner on the image. 9 8 7 6 B 5 4 3 A 2 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Describe the transformation that maps A onto B. Scale factor 2 Draw a line all the way through these points. 9 8 7 6 B 5 4 3 A 2 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Describe the transformation that maps A onto B. Scale factor 2 Repeat with another pair of vertices. 9 8 7 6 B 5 4 3 A 2 1 0 0 1 2 3 4 5 6 7 8 9 10

13 December 2021 Enlargement 10 Describe the transformation that maps A onto B. Scale factor 2 Centre (1, 0) The point where the lines cross is the centre of enlargement. 9 8 7 6 B 5 4 3 A 2 1 0 0 1 2 3 4 5 6 7 8 9 10