-12 < -6x
-12/-6 > x divide both sides by -6
12/6 > x two negatives makes a positive
2 > x simplify
x < 2 switch sides
hope this helps, God bless!
Answer:
F(x)=2x^2
Step-by-step explanation:
Basically, a quadratic function has x^2 in it (standard form ax^2+bx+c with non-zero a). The others have x^3, -x, x^4, etc., which clearly are NOT x^2.
2 42/100 turn it to a fraction
For any equation,

assume solution of a form, 
Which leads to,

Simplify to,

Then find solutions,

For non repeated real root y, we have a form of,

Following up,
For two non repeated complex roots
where,

and,
the general solution has a form of,

Or in this case,

Now we just refine and get,

Hope this helps.
r3t40