The answer is 3b. hope it helps
ANSWER
The substitution property of equality.
EXPLANATION
We know that:
![12x = 60](https://tex.z-dn.net/?f=12x%20%3D%2060)
and that
![x = 5](https://tex.z-dn.net/?f=x%20%3D%205)
Since x=5 or 5=x , we can substitute x for 5 wherever we see x in the given equation.
When we do that, we obtain;
![12 \bullet \: 5 = 60](https://tex.z-dn.net/?f=12%20%5Cbullet%20%5C%3A%205%20%3D%2060)
This is what we refer to as the substitution property of equality.
The answer is going to be = 4m + 19
That is what you get after doing all the math