↔️ The Mirror Maker — Reflections
Master all four mirror line types · Build the instinct for coordinate rules · Ace the 4MA1 exam
Logic Track
Phase 1 · Anchory = 0 (x-axis)
y = 0 is the x-axis — a HORIZONTAL mirror line.
The y-coordinate flips sign. The x-coordinate stays the same.
📐 Coordinate Rule
Negate the y-coordinate.
⚠️ Examiner Trap
Trap: y = 0 is HORIZONTAL, not vertical! The axis name tells you which axis it lies on.
🔑 Golden Rule
"Count the steps to the mirror — then take the exact same number of steps out the other side."
The perpendicular distance from any point to the mirror line is always equal on both sides.
Dynamic Solver — Coordinate Reflector
Mark Scheme Step-by-StepRule: Reflect in y = 0 (x-axis). Negate the y-coordinate.
(x, y) → (x, −y)
(4, 1) → (4, −1)
🗺️ All Reflection Rules (Cheat Sheet)
⚠️ Exam Tip: x = a is VERTICAL. y = b is HORIZONTAL. The variable tells you which axis it parallels.
⚓ Phase 1 · Anchor
y = 0 or x = 0
The axes are your first mirrors. y = 0 flips up/down. x = 0 flips left/right.
🔀 Phase 2 · Twist
x = a or y = b
Shifted mirrors. Find the distance from the line — go the same distance to the other side.
⚡ Phase 3 · Killer
y = x or y = −x
Diagonal mirrors. Swap coordinates (y=x) or swap AND negate (y=−x). Multi-step AO3 territory.
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