Reflection — Grade 8 Math, what it means and where it is taught
A flip across a line, like a mirror.
Taught in Grade 8 Math.
Where it is taught
Practise this idea
2 questions in the course bank use Reflection, in Translations, Reflections & Rotations.
Problem 1
Point (5, -2) maps to (-5, -2). Which single transformation was used?
Worked answer
reflection across the y-axis
The x changed sign; the y did not
That is the rule (x, y) → (-x, y)
A reflection across the y-axis
Problem 2
A point is reflected across the y-axis and then translated 4 right. The final image is (1, 6). Find the original point.
Worked answer
(3, 6)
Undo the translation: (1 - 4, 6) = (-3, 6)
Undo the reflection: (3, 6)
Check: (3,6) → (-3,6) → (1,6) ✓