Answer:
x = 31°
Step-by-step explanation:
Since, CB ║ FG and AB is a transverse, so ∠ BAG = ∠ ABC = 28° {Alternate angles}
Now, ∠ CAG = 90° = ∠ CAD + ∠ BAG
⇒ ∠ CAD = 90° - 28° = 62°
From, Δ ADE, ∠ ADE + ∠ DEA + ∠ EAD = 180°
⇒ ∠ ADE = 180° - 62° - 3x = 118° - 3x.
Now, ADB being a straight line, so ∠ ADE + ∠ EDC + ∠ CDB = 180°
⇒ 118 - 3x + x + 4x = 180
⇒ 2x = 62
⇒ x = 31° (Answer)