doing some basic personal finance question here and for the life of me just cant figure it out.

here is the equation: (1 + x)(0.20) - x(0.10) = 0.26

trying to solve for x, but I just can't figure it out. I know the answer is 0.6, but how the fuck do you get it? Should be a pretty straight forward question....me = Dunce, I guess.