## Algebra 1: Common Core (15th Edition)

For every question the student misses, she loses points off of her score, so we know that the slope is negative. We are given two points: (1, 98) and (5, 90). (Note, the score on the test is the dependent variable as it depends on how many points the student misses). In order to find the slope, we use the following equation: $\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$. Thus, we obtain: $\frac{98-90}{1-5}=\frac{8}{-4}=-2$