Step-by-step explanation
If x+2 is a factor, we need to equal the factor to zero, isolate x and substitute the value into the function:

Plugging in x=-2 into the function:

Computing the powers:

Multiplying numbers:

Adding numbers:

Adding +6m to both sides:

Dividing both sides by 6:

Simplifying:

In conclusion, the value of m is 12