I’m not sure I would help you if knew
In the pattern, the values are increasing by 22 each time so for the 117th term you take 57 + 22 = 79
So, 117= 79
Translation does not affect length.
So the length of E'F' is 5 units.
-136 = 8m - 8
-136 + 8 = 8m
-128/8 = m
-16 = m
M = -16