Line of Best Fit, Interpolation, and Extrapolation (HSC SSCE Mathematics Standard): Flashcards

Straight line representing linear association on scatterplot

$y = mx + c$

Gradient (slope) of the line

$y$-intercept (where line crosses vertical axis)

Points roughly balanced above and below the line

Change in dependent variable per 1 unit increase in independent

Estimating values within the range of existing data

Predicting values outside the range of existing data

Generally reliable, especially with strong linear association

Less reliable; linear relationship may not continue beyond data