The derivative of 100 minus x with respect to x is just negative 1. So times negative 1. Times, so we'll multiply negative 1 right over here. And so we can rewrite all of that as this is going to be equal to the square root of 3 over 18x plus, let's see, I could write this as positive x over 8. So I could write this as 1 8th x, because negative 1 times negative x is positive x over 8. And then minus 100 over 8, which is negative 12.5. Minus 12.5.