every input
its output
x = −1
x = 0
x = 1
x = 4
6
2
0
6
the same pairs, drawn as points
three relations
one input, two outputs
36 ft²
24 ft
26 ft
two inputs, one output
x = −1
x = 4
f = 6
four tidy rows
2020 → Lil Tecca
2021 → Olivia Rodrigo
2022 → Forrest Wheeler
2023 → Miles Brown
2021 → Olivia Rodrigo
2022 → Forrest Wheeler
2023 → Miles Brown
feed it 2020 again —
Lil Tecca, or any of the
millions of others?
Lil Tecca, or any of the
millions of others?
Wait — that’s a
repeat. Doesn’t that break it?
Integrated Math 1 · §1.3.2
What makes a relationship
a function
and why “no repeats” is the wrong rule