The equation x² - 4 = 0 is a simple quadratic equation. It can be rewritten as x² = 4, which means we are looking for the values of x that, when squared, equal 4. To solve for x, we take the square root of both sides. This gives us two possible solutions: x = 2 and x = -2. These solutions represent the points where the graph of the equation intersects the x-axis, known as the roots of the equation.