Which ones are functions?
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Answer:
The first, second, third, and fourth
Step-by-step explanation:
Each input in the first, second, third, and fourth only have one output. In the fifth one 3.3 and 6.6 are seen twice as the x-value, so this is incorrect.
Cada entrada en la primera, segunda, tercera y cuarta tiene solo una salida. En el quinto, 3.3 y 6.6 se ven dos veces como el valor de x, por lo que esto es incorrecto.