Answer:
20
Explanation:
Let the angle at the left corner is A, so the angle at the rIght corner should be (180-90-A) = (90-A).
In the left triangle:
tanA = 8√5/16 = √(5)/2
Thus,
cotA = 1/tanA = 2/√5
In the right triangle:
tan(90-A) = 8√5/x
cotA = 8√5/x [tan(90-x) = cotx]
2/√5 = 8√5/x
x = 20