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Current time:0:00Total duration:1:07

Worked example: matching an input to a function's output (graph)

Video transcript

the graph of the function G is shown below what is the input value for which G of X is equal to negative 2 so what they do over here is along the x-axis these are the inputs and then the graph shows us what's the output so when X is equal to 7 G of 7 we see here is 1 if x equals 9 G of 9 here is 2 if x equals 6 G of 6 is equal to the y-coordinate at this point is equal to 0 so what is the input value for which G of X is equal to negative 2 well this graph right over here this is y equals G of X so G of X equaling negative 2 means Y is equal to negative 2 and so when does y equal negative 2 well when does y equal negative 2 it looks like that happens right at this point and that happens when you input negative 9 into G G of negative 9 is negative 2 so this is going to be negative 9 and we're done