Question

For what x-value of x-values does f(x) = 3 on the following graph?

Answer 1

To find the x- value at which f(x) = 3

Draw a horizontal line y = 3 ,and find the intersection between the line and the f(x)

See the following image :

As we can see, when f(x) = 3

x will be equal 6

so, the answer is x = 6