You can put this solution on YOUR website! Without graphing, to find the minimum value, you need to look at the terms and see which one(s) can change. You know that is a constant, so that one won't change. You can see that the first term involves a factor of that includes a square. You know that the minimum a squared value can be is 0 (A squared value is always going to be positive or 0).
So the minimum value occurs when the first term is 0.
So what value of x makes
When x = -12.68, then