Ms. Bradley made a scatter plot with her students' individual homework averages on the x-axis and their individual average test scores on the y-axis, with both x
and y as integers between 0 and 100. She calculated the equation of the line of best fit as y=0.8z +18.
Jillian, one of Ms. Bradley's students, had a homework average of 70 and a residual of -6. What was Jillian's average test score?