The answer is c, 8/3 (6) - 16 = 0 therefore 6 is the zero
The solution is (-2,4) she right both have the same solution because if you solve both of them you will get (-2,4)
In commission he made $30, and in all he made 780$
Slope = (y2 - y1)/(x2 - x1) = (10 - 70)/(5 - (-15)) = -60/(5 + 15) = -60/20 = -3