(a) The denominator requires \(y>0\). Let \(u=\sqrt y>0\). Multiplying by \(u\) gives \[6u^2-7u+2=(2u-1)(3u-2)=0.\] Thus \(u=1/2\) or \(2/3\), giving \[y=\frac14\text{ or }\frac49.\]

(b) Hence \(\tan x=1/4\) or \(4/9\). Tangent is positive in quadrants I and III. The four values are \[x\approx14.0^\circ,\quad24.0^\circ,\quad194.0^\circ,\quad204.0^\circ.\] Each has positive, finite tangent and satisfies the original radical equation.