Question

the equation for the line of best fit is y = \frac{2}{5}x + 7. according to the equation, which of these statements is true? the number of salmon increases by about 5 salmon every 2 days. the number of salmon increases by about 4 salmon every 10 days.

Explanation:

Step1: Identify the slope

The equation of the line is $y=\frac{2}{5}x + 7$, and the slope $m=\frac{2}{5}$.

Step2: Calculate change for 2 - day period

For a 2 - day period ($x = 2$), $y_2 - y_1=m\times2=\frac{2}{5}\times2=\frac{4}{5}$, not 5.

Step3: Calculate change for 10 - day period

For a 10 - day period ($x = 10$), $y_2 - y_1=m\times10=\frac{2}{5}\times10 = 4$. So the number of salmon increases by about 4 salmon every 10 days.

Answer:

The number of salmon increases by about 4 salmon every 10 days.