Answer: The value necessary from the set to make the equation true was 11.
Step-by-step explanation:
Process of elimination:
1. 2([10]-5)
= 2(5)
= 10, not 12.
2. 2([11]-5)
= 2(6)
= 12; the answer we need.
We substituted x for 11, and then the equation worked; so therefore the value we needed from the set was 11.
