tolong dijawab ya beserta caranya

Pertama cari garis miring dulu (C)
C^2 = A^2 + B^2
C^2 = 10^2 + 10^2
C^2 = 100 + 100
C^2 = 200
C = 10√2
Berarti X = 10√2 - 2 = 8√2

Lalu cari Y. Misal Y = B, C = X
B^2 = C^2 - A^2
B^2 = (8√2)^2 - 6^2
B^2 = 128 - 36
B^2 = 92
B =  2√23