Answer:
x = 6
Step-by-step explanation:
Slope = (y(2) - y(1))/(x(2) - x(1))
(-1 - 1) / (-1 - x)
If the slope is 2/7, it would be (-2/-1-x, where x would have to be 6)
(-2)/(-7) = 2/7, so x = 6
Check:
(-1 - 1) / (-1 - 6)
(-2)/(-7)
2/7 (Correct :))
Hope it helps :D