1. The problem is to provide the formula used for solving a math problem. 2. Generally, the formula depends on the type of problem. For example, for solving a quadratic equation $ax^2 + bx + c = 0$, the quadratic formula is used: $$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$ 3. This formula calculates the roots of the quadratic equation by substituting the coefficients $a$, $b$, and $c$. 4. Important rules: - The discriminant $\Delta = b^2 - 4ac$ determines the nature of the roots. - If $\Delta > 0$, there are two distinct real roots. - If $\Delta = 0$, there is one real root (a repeated root). - If $\Delta < 0$, the roots are complex. 5. To use the formula, identify $a$, $b$, and $c$ from your equation, compute the discriminant, then substitute into the formula to find the roots. This is a common formula used in algebra for quadratic equations.