You need to remember that `arcsin(sin x) = x` , hence you may write the equation in terms of x such that:
`0.25 = x + x/2 =gt 1/4 = x + x/2`
You need to bring the terms to a common denominator such that:
`1 = 4x + 2x =gt 6x = 1 =gt x = 1/6`
Hence, evaluating the solution to equation yields `x = 1/6` .