The like terms are 12 and 5, so you have to subtract 5 from both sides.
12 < x + 5
-5. -5
7 < x
We can just switch it around so x is in the left side.
x > 7
What’s the question?
.????????
Answer: C
ABCD may or may not be a parellolgram. Line BD bisects line AC, however we cant figure out if line AC bisects line BD.
First, square both sides. This will cancel out the radical.

(a^2 = b + 6)
Then subtract 6 from both sides
b = a^2 - 6