To find the x-intercepts of the function f(x) = x² + 4x – 12, we need to set the function equal to zero and solve for x.
So, we start with:
x² + 4x - 12 = 0
This is a quadratic equation, which we can solve by factoring, completing the square, or using the quadratic formula. In this case, let’s try factoring.
We look for two numbers that multiply to -12 (the constant term) and add to 4 (the coefficient of the x term). These numbers are 6 and -2.
Thus, we can factor the equation as:
(x + 6)(x - 2) = 0
Next, we set each factor equal to zero:
x + 6 = 0
x - 2 = 0
Solving these gives us:
x = -6
x = 2
So, the x-intercepts of the graph are at the points (-6, 0) and (2, 0). This means the graph crosses the x-axis at these two points.