Final Answer:
The value of the quadratic expression
+ 6x + 8 when x = -2 is 0.
Step-by-step explanation:
The given quadratic expression is
+ 6x + 8. To evaluate this expression for a specific value of x, in this case, x = -2, we substitute -2 for x in the expression:
![\[(-2)^2 + 6(-2) + 8\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/xw4a7uhzwnennztnifp14zjshcu9hcmwy7.png)
Simplifying this expression step by step:
![\[= 4 - 12 + 8\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/xr4om0c2fnhjexyp4ryyzqxx9mpsi4yet2.png)
![\[= 0\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/ez5mbpplgh3bos23o5p4fokbo0rjfk1jt7.png)
Therefore, when x = -2, the value of the quadratic expression
+ 6x + 8 is 0. This means that (-2) is a root of the quadratic equation, making the expression equal to zero.
In the quadratic expression,
+ 6x + 8, we can also determine its factors by factoring:
![\[x^2 + 6x + 8 = (x + 2)(x + 4)\]](https://img.qammunity.org/2024/formulas/mathematics/high-school/vwjwjnctqjri8ki3ueafvdhq0jmmvf53c2.png)
Setting each factor equal to zero and solving for x gives the roots of the quadratic equation. In this case, when (x + 2) = 0, x = -2, and when (x + 4) = 0, x = -4.
So, the quadratic expression has roots at x = -2 and x = -4. Substituting x = -2 into the expression verifies that it indeed evaluates to 0, confirming the root of the quadratic equation at x = -2