the answer is A
AO = 12
BC= 25+ 12= 37
you can get help from Pythagoras theorem
[tex] {37}^{2} = {12}^{2} + {x}^{2} \\ - {x}^{2} = {12}^{2} - {37}^{2} \\ - {x}^{2} = 144 - 1369 = - 1225 \\1225 = {x}^{2} [/tex]
[tex]x = \sqrt{1225} = 35[/tex]
good luck
