x=30
since 106 and the interior angle of the second triangle form a linear pair, the angle must equal 74. As you know, a triangles interior angles must add up to 180, and since we have the two angles 31 and 74, the third angle must be 75
With this we have another linear pair with the other triangle, meaning the interior angle would be 105. Again, the interior angles must add up to 180, and since we have 105 and 45 the last angle is 30.
Then, since it’s a vertical angle with x, they are equal making x= 30