Answer
$H$
Work Step by Step
Before we solve this equation, we can see that a $7$ can be factored out:
$7(x^2 + 28) = 0$
Divide both sides by $7$:
$x^2 + 28 = 0$
Subtract $28$ from both sides of the equation to isolate the $x$ term:
$x^2 = -28$
Take the square root of both sides:
$x = \sqrt {-28}$
Let's expand the radicand and rewrite it as a product of a square and another number:
$x = \sqrt {(-4)(7)}$
We take the square root of $-4$ to take it out from under the radical sign:
$x = ± 2i \sqrt {7}$
This corresponds to option $H$.
