Respuesta :
Answer:
draw a strait line and if it doesn't touch another dot it is a function
Step-by-step explanation:
Answer: Vertical line test
Step-by-step explanation:
Look at one of the graphs you have a question about. Then take a vertical line and place it on the graph. If the graph is a function, then no matter where on the graph you place the vertical line, the graph should only cross the vertical line once.