Write that down the equation for the lines that is the graphs are depicted below PLZ HELP 20 points

The center of a circle represent by the equation (x+9)^2+(y-6)^2=10^2 (-9,6), (-6,9), (6,-9) ,(9,-6)

Evaluate the expression for the given value of the variable 7a - 4a for a =8

Afrequency table of grades has five classes (a, b, c, d, f) with frequencies of 3, 13, 14, 5, and 3 respectively. using percentages, what are the relative frequencies of the five classes?