Solve the inequality x^2 + 7x + 12 < 0.

To solve the inequality x^2 + 7x + 12 < 0, we can use a method called factoring.

Step 1: Rewrite the inequality.

x^2 + 7x + 12 < 0

Step 2: Factor the quadratic expression on the left side.

(x + 3)(x + 4) < 0

The factors of the quadratic expression are (x + 3) and (x + 4).

Step 3: Determine the sign of each factor.

To determine the sign of each factor, we need to find the values of x that make each factor equal to zero.

(x + 3) = 0 --> x = -3
(x + 4) = 0 --> x = -4

Step 4: Create a sign chart.

We will create a sign chart using the critical values (-3 and -4).

-4 -3 0
+ - + +

Step 5: Analyze the sign chart.

From the sign chart, we can see that the expression (x + 3) is positive for x < -3 and negative for x > -3. Similarly, the expression (x + 4) is positive for x < -4 and negative for x > -4.

Step 6: Determine the solution.

To find the values of x that satisfy the inequality, we want to find the intervals where the expression (x + 3)(x + 4) is negative.

From the sign chart, we can see that the expression is negative between -4 and -3:

-4 < x < -3

Therefore, the solution to the inequality x^2 + 7x + 12 < 0 is -4 < x < -3.