I’m not how to explain this but bear with me.
The supplement of measure of 164 degree angle is 16 degrees.
The bigger triangle is a right triangle, meaning it has an angle of 90 degrees.
We can find the big angle on the top by adding both angles we know of together and subtract that from 180 degrees because all interior angles of a triangle add up to 180 degrees:
180 - (90 + 16) = 180 - 106 = 72 degrees
According to the picture, the angle appears to be bisected, meaning it has been divided into two congruent angles.
Take the 72 degree angle and divide it by 2 to get the measure of each angle. Each angle is 36 degrees.
Finally, add the measures of the 36 degree and 16 degree angle and subtract that from 180 degrees to get the measure of the unknown angle (the value of x).
180 - (36 + 16) = 180 - 52 = 128 degrees
x = 128 degrees
I think this is the answer.