Exact expressions from cosine ratios

Without using a calculator, evaluate each of the following.

1. if \(\cos x^\circ=5/13\), where \(x\) is acute, find \(2\sin x^\circ+\cos x^\circ+3\tan x^\circ\)
2. if \(\cos y^\circ=8/17\), where \(y\) is acute, find \(\tan(90^\circ-y^\circ)\)