lesson
Updated 1 month ago · 6 views
What if you could draw only half of a picture, and a magic glass finished the other half for you?
A small flat mirror can do just that! When a shape has symmetry, one half matches the other half like twins looking at each other.
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Where should you place your mirror to test if a shape has matching halves?
The Center Line
The middle fold of a shape is called the line of symmetry or center line.
Stand your mirror straight up, directly on this center line. If the shape is symmetrical, the reflection in the glass will complete the whole shape perfectly.
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What happens if a shape does not have matching sides?
Passing and Failing the Test
Let's test two different shapes with our mirror: a star and a shoe.
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Why do some shapes look strange even when we know they have matching sides?