Answer:
x = 8
Step-by-step explanation:
m = [tex]\frac{y_{2} -y_{1} }{x_{2} -x_{1} }[/tex]
(6, 11)
(x, 15)
m = 2
[tex]\frac{15-11}{x-6}[/tex] = 2
2(x - 6) = 15 - 11 ⇒ x = 8