tanα=h/x
x=h/tanα
x=70/tan38 ft
x≈89.6 ft (to nearest tenth of a foot)
Note: the question seems strange, (because this would make the ladder almost 114 feet long!) or are we to assume as I did that the ladder is leaning against a point 70 feet high, or should if be a 70 foot ladder leaning against a wall of unknown height?
If it is just a 70 ft ladder at a 38° inclination the:
cosα=x/L
x=Lcosα
x=70cos38° ft
x≈55.2 ft