So we're not going to get our critical point by figuring out where the derivative is undefined. But we might get a critical point by setting this derivative equal to 0 to figure out what x values make our derivative 0. When do we have a 0 slope for our original function? And then we just have to verify that this is going to be a minimum point. If we can find an x, it makes this thing equal to 0. So let's try to solve for x. So if we add 12.5 to both sides, we get 12.5 is equal to, if you add the x terms, you get square root of 3 over 18 plus 1 8th x.