Normally a domestic freezer is best set to â18 Â°C (0 Â°F) or colder, as that's what the expiration dates for many food items are based on. It's also a requirement for freezers in restaurants, supermarkets & other places that sell food (at least here in Europe) to maintain a temperature of at most -18 Â°C.
Note: When you're dealing with quadratic equations, it can be really helpful to identify a, b, and c. These values are used to find the axis of symmetry, the discriminant, and even the roots using the quadratic formula. It's no question that it's important to know how to identify these values in a quadratic equation.
But we'll start with solving by factoring. You should already know how to factor quadratics. (If not, review Factoring Quadratics .) The new thing here is that the quadratic is part of an equation, and you're told to solve for the values of x that make the equation true. Here's how it works: 1  Solve (x â 3)(x â 4) = 0.his equation is not in (quadratic) equals (zero) form, so I can't try to solve it yet. The first thing I need to do is get all the terms over on one side, with zero on the other side. Only then can I factor and solve: x2 â 3 = 2x x2 â 2x â 3 = 0 (x â 3)(x + 1) = 0 x â 3 = 0 or x + 1 = 0 x = 3 or x = â1.