So∠DHG = 7x-42, and since ∠FHC is directly opposite of it, it's the same value, 7x-42.
∠AGH should equal ∠CHF since they're both on parallel lines and line EF intersects them.
Therefore, ∠AGH =∠FHC:
3x-10=7x-42 (Subtract 7x and -10)
-4x=-32
x=8
∠DHG should be 8°
