Given,
tanθ=815
Let, θ=∠A
We know that,
tanθ=oppositeSideadjacentSide
Consider the figure above,
From Pythagoras theorem,
AC2=AB2+BC2
AC2=152+82
AC2=225+64=289
AC=17
sinθ=oppositeSideHypotenuse=817
cosθ=AdjacentSideHypotenuse=1517
cscθ=1sinθ=1817=178
secθ=1cosθ=11517=1715
cotθ=1tanθ=158