Answer:
Part 1) Option B. y = 10x + 45
Part 2) The score is 95
Explanation:
Linear equation that best describes the given model 
 
Let 
 
x ---> number of hours students spent studying 
 
y ---> their score on the test 
 
Looking at the line that was fit to the data to model the relationship 
 
The slope is positive 
 
The y-intercept is the point (0,45) 
 
For x=1, y=55 ----> point (1,55)
Find the slope 
 
The formula to calculate the slope between two points is equal to 
 
 
 
substitute the points (0,45) and (1,55) 
 
 
 
Find the equation of the line in slope intercept form 
 
 
 
we have 
 
 
 
substitute 
 
 
 
Part 2) Estimate the score for a student that spent 5 hours studying. 
 
For x=5 hours 
 
substitute in the linear equation and solve for y