Draw altitude AE
Then DE = (3 -1) / 2 = 1
And we have right triangle ADE with legs of sqrt 2 , 1 and the trapezoid height as the other leg
So
h = sqrt [( sqrt 2)^2 - 1 ] = 1
And we also have right triangle AEC where EC = 2
So
x = sqrt [ 2^2 + 1^2 ] = sqrt 5
Draw line AM so it is perpendicular to DC
Trapezoid ABCD is isceles, meaning DM=1
Applying the Pythagorean Theoram to △AMD, we find that AM=1
Applying the Pythagorean Theorem to △AMC, we find x=√5