Q 4. - Precalculus Enhanced with Graphing Utilities

Question

If the independent variable in a line of best fit $y=-0.008x+14$ is credit score, and the dependent variable is the interest rate on a used car loan, then the slope is interpreted as “if credit score increases by $1$ point, the interest rate will                    (increase/decrease) by                   percent, on average.

Step-by-Step Solution

Answer

If the independent variable in a line of best fit $y=-0.008x+14$ is credit score, and the dependent variable is the interest rate on a used car loan, then the slope is interpreted as “if credit score increases by $1$ point, the interest rate will decrease (increase/decrease) by $0.008$  percent, on average.

Step 1. Define increasing and decreasing function.

If the slope ($m$) of a linear function $y=mx+b$ is positive, it increases throughout its domain and if the slope ($m$) is negative, it decreases over its domain.

Step 2. Fill the blank in the given statement.

If the independent variable in a line of best fit $y=-0.008x+14$ is credit score, and the dependent variable is the interest rate on a used car loan, then the slope is interpreted as “if credit score increases by $1$ point, the interest rate will decrease (increase/decrease) by $0.008$ percent, on average.