The required quadratic equation is found using the sum and product of roots formula, x^2 - (sum of roots)x + (product of roots) = 0. Substituting the given values alpha + beta = -4 and alpha * beta = -3 into the formula gives x^2 - (-4)x + (-3) = 0. Simplifying this expression results in the equation x^2 + 4x - 3 = 0.