Therefore, x = 1° and ∠DAB = 4°.
Since ∠DAB is bisected by AD, we have ∠DAB = ∠BAD.
From the diagram, we can see that ∠A + ∠B + ∠C + ∠D = 180°.
Substituting ∠DAB = ∠BAD, we get 2∠DAB + ∠B + ∠C = 180°.
Since ∠A and ∠C are opposite angles, we know that ∠A = ∠C.
Substituting ∠A = ∠C, we get 2∠DAB + ∠B + ∠A = 180°.
Therefore, ∠A + ∠B + ∠DAB = 90°.
From the diagram, we can see that ∠DAB + ∠B + ∠BAD = 90°.
Substituting ∠DAB = ∠BAD, we get 2∠DAB + ∠B = 90°.
Therefore, ∠DAB = (90° - ∠B)/2.
Since we are given that AD is an angle bisector, we know that ∠DAB = ∠BAD.
Substituting ∠DAB = ∠BAD, we get (90° - ∠B)/2 = ∠BAD.
Therefore, ∠BAD = (90° - ∠B)/2.
From the diagram, we can see that ∠A + ∠BAD = 90°.
Substituting ∠BAD = (90° - ∠B)/2, we get ∠A + (90° - ∠B)/2 = 90°.
Therefore, ∠A = ∠B/2.
Now we can solve for x and ∠DAB.
From the diagram, we can see that ∠A = -2x + 10° and ∠B = -4x + 12°.
Substituting ∠A = ∠B/2, we get -2x + 10° = (-4x + 12°)/2.
Solving for x, we get x = 1°.
Substituting x = 1° into the expression for ∠DAB, we get ∠DAB = (-2(1°) + 10°)/2 = 4°.