lesson

Updated 6 days ago Β· 2 views
Imagine hiding a gold coin on a giant checkered game board. How could you tell your best friend the exact square to find it?
We use a grid, which is a flat surface made of lines that cross to make square spaces.
Every spot on the grid has a special address called an ordered pair, written inside curved brackets like (x,y).
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Why do the two numbers always have to be in this exact order?
Walk Along, Then Jump Up
Long ago, a thinker named RenΓ© Descartes watched a fly crawl on his ceiling tiles and realized he could pinpoint its spot with just two numbers.
We always follow one golden rule: x comes first (walk across), and y comes second (jump up), just like the letters in the alphabet!
πInteractive diagram
How do we use this rule to find a hidden treasure at (4,3)?
Finding a Point
Start with your finger at zero. The first number in (4,3) tells you to slide right 4 spaces along the ground.
From that exact spot on 4, the second number tells you to climb straight up 3 spaces.