Mathematics Geometry Conceptual 12–14 yrs

Coordinates (age 12+)

坐标（12岁以上）

Description

Understand similarity as a relationship where one shape is an enlargement of another; construct similar shapes by enlargement with a given scale factor and centre, with and without coordinate grids

Mastery Evidence

✓ Enlarge a shape by a given scale factor from a specified centre of enlargement
✓ Determine the scale factor between two similar shapes by comparing corresponding sides
✓ Explain why corresponding angles in similar shapes are equal while sides are in proportion

Assessment Prompt

If your child wants to enlarge a photo so it's three times bigger, can they work out the new dimensions — and explain that the shape stays the same but all lengths increase by the same factor?