To determine the line of best fit using a calculator, you need to input your data and utilize the linear regression function.

Start by ensuring that you have a set of paired data points, typically represented as $(x, y)$. Enter these data points into your calculator. Most scientific and graphing calculators have a dedicated mode or function for statistical calculations. For instance, on a Casio calculator, you can access this by pressing the ‘MODE’ button, selecting ‘STAT’, and then choosing the linear regression option, which is often labeled as $A + BX$ or something similar.

Once you are in the appropriate mode, input your $x$-values and $y$-values. This is generally accomplished by entering each $x$-value followed by its corresponding $y$-value. After all data points have been entered, use the calculator’s function to compute the line of best fit. This function is usually indicated as ‘Reg’ or ‘LinReg’ on the device.

After executing this function, the calculator will present you with the equation of the line of best fit in the form:

Here, $a$ represents the slope, and $b$ denotes the y-intercept. Additionally, some calculators may provide further statistical information, such as the correlation coefficient, which measures how well the line fits the data.

By following these steps, you can efficiently find the line of best fit—a vital tool for analyzing data trends and making predictions based on your dataset.