Identify the classification system that corresponds to each description. Uses numbers:
Uses letters:
Used internationally:
Used mainly in U. S. colleges and universities:

answers,,

Library of congress system

Dewey Decimal System

  or  

sin y = 7/q

7 is the opposite side length, q is the hypotenuse

tan y = 7/r

7 is the opposite side length, r is the adjacent side length

using sohcahtoa ^^^^

cos y = adjacent/hypotenuse

cos y = r/q

this would be 35. 35 + 5 = 40. you take the known constant and subtract by the answer of the equation and you get y.