Daniel B. answered 02/01/21
A retired computer professional to teach math, physics
Let
α be the angle to the left of the 68° angle,
β be the angle to the right of the 68° angle,
Y be the remaining angle in the triangle with angles β, X, Y
v be the perpendicular distance from the vertex of Y to the line connecting β and X.
Then we have the following four identities with four unknowns
α + β + 68° = 180° (1)
tan(α) = 15/25 (2)
sin(β) = v/25 (3)
sin(X) = v/35 (4)
From (2)
α = 30.96375653°
From (1)
β = 81.03625347°
From (3)
v = 25 sin(β) = 24.69467746
From (4)
sin(X) = 0.705562213
X = 44.87498231°
X = 135.1250177°
The problem has two solution.
The solution of about 45° is the one suggested in the picture.
The other solution of about 135° is also a perfectly valid solution,
if we were not required to interpret the picture as being to scale.