$U(x_1, x_2) = 1/2 * x_1 $
I am trying to calculate the Hicksian demand when when $U(x_1, x_2) = 2$ and the value of the minimum expenditure when $p_1 = 9$ and $p_2 = 16$
For the hicksian demand I tried using Lagrange but it did not work out as the partial derivatives turned out to be only constants, not equations. I'm not completely sure if I should substitute with $p_1$ and $p_2$ at any point.
Am I missing something ? Is there another way to solve this kind of problems without using Lagrange and in a more straightforward manner ? Any help is appreciated.