5)
For a right triangle, the cosine of an angle is the ratio between the length of the adjacent side and the length of the hypotenuse (the hypotenuse is the longest side of the triangle).
In this case,
cos(A) = adjacent / hypotenuse = 30 / 34 = 15/17
6)
For a right triangle, the cosine of an angle is the ratio between the length of the opposite side and the length of the hypotenuse.
In this case,
sin(A) = opposite / hypotenuse = 32 / 40 = 4/5
A way to remember sine, cosine, and tangent is SOHCAHTOA, where
SOH is Sine = Opposite / Hypotenuse
CAH is Cosine = Adjacent / Hypotenuse
TOA is Tangent = Opposite / Adjacent
