Question

the equation for the line of best fit is $y = 10x + 50$.\
which of the following is a valid prediction based on this equation?\
if the temperature rises $1^circ$f, there will be exactly 10 more attendees.\
if the temperature rises $1^circ$f, there should be about 50 more attendees.\
on a $50^circ$f day, there should be about 100 attendees.\
on a $50^circ$f day, there should be about 550 attendees.

Explanation:

Step1: Identify variables in the equation

Assume \(x\) = temperature (°F), \(y\) = attendees. The equation is \(y = 10x + 50\).

Step2: Analyze slope interpretation

Slope = 10 means for 1°F rise, attendees increase about 10 (not exactly), so first two options are wrong.

Step3: Calculate \(y\) when \(x=50\)

Substitute \(x=50\) into the equation: \(y = 10(50) + 50 = 550\). So the fourth option is correct.

Answer:

On a 50°F day, there should be about 550 attendees.