Answer:
p = 6
Step-by-step explanation:
The slope equation is:
[tex]m = \frac{y \frac{}{2} - y \frac{}{1} }{x \frac{}{2} - x \frac{}{1} } [/tex]
then to know the value of "p":
[tex] - \frac{1}{3} = \frac{7 - p}{p - 9} \\ - 1(p - 9) = 3(7 - p) \\ - p + 9 = 21 - 3p \\ 3p - p = 21 - 9 \\ 2p = 12 \\ p = \frac{12}{2} \\ p = 6[/tex]
