Answer:
30 units
Explanation:
If point G is on line segment FH, then point G lies between points F and H.
Segment Addition Postulate states that given 2 points F and H, a third point G lies on the line segment FH if and only if the distances between the points satisfy the equation FG + GH = FH.
By segment addition postulate,

Given
FH = 4x,
GH = x,
FG = 2x + 10,
then
