Answer:
The real solutions to a equation is given by the x-intercept. Therefore, if you know the graph to a equation, then we can know the solution to that equation just by looking at the points where the graph intercepts the x-axis.
If you have a table, you can plot the data contained in the table. Then, you can add best fit line/curve to the data set, and look at the points where the curve intercepts the x-axis.