The quadratic formula is a mathematical tool used to find the solutions of quadratic equations, which are equations in the form of ax² + bx + c = 0. The formula is expressed as x = (-b ± √(b² - 4ac)) / (2a). Here, a, b, and c are coefficients from the equation, and the symbol "±" indicates that there are usually two possible solutions for x. To use the quadratic formula, first identify the values of a, b, and c from the equation. Then, substitute these values into the formula. Calculate the discriminant, b² - 4ac, to determine the nature of the solutions. If the discriminant is positive, there are two real solutions; if it is zero, there is one real solution; and if it is negative, the solutions are complex numbers.