The answer is D. 7x squared - 2x + 4
Using the Quadratic formula
your answer would be A and C
Express in simplest a+bi form: Square root of 1b + Square root of -1b

Lets simplify 
We know 

We cannot simplify 


So a + ib form is 
Answer:
Step-by-step explanation:

First, on the right-hand side of the equation, let's distribute the
to each term in the parenthesis:

Now, let's move all the terms with an
to the left-hand side, and everything else to the right-hand side of the equation:

Let's combine like terms:

Finally, let's divide each side by
to get
by itself on the left-hand side of the equation:
