Consider the quadratic function that models U.S. Population percentage for foreign born as shown below:

, where is the number of years after 1900.

(a)

Verify the graphical solution one of the solution to the model is.

Sketch the graph of the quadratic function:

After sketching the graph, sketch the graph and on the same window.

Both lines and intersect the graph at the point, which verifies the is the solution of the quadratic equation.