Tangent of an acute angle in a right triangle is (opposite side)/(adjacent side).
Tangent (52°) = (CB) / 8.5
Multiply each side by 8.5 :
CB = 8.5 times tangent(52°)
Use a calculator, internet search, or book to find tangent(52°).
Tangent(52°) = 1.28
CB = (8.5) · (1.28)
CB = 10.88
