Answer:
[tex]x=+2i\sqrt{14}\ \ \,x=-2i\sqrt{14}[/tex]
Step-by-step explanation:
[tex]-3x^2-168[/tex]
The first step in solving this equation is the factor, remove a factor that both the quadratic and constant term have in common. In this case, such a term would be (-3),
[tex]-3(x^2+56)[/tex]
Now set the equation equal to zero so that one can use the zero product property. The zero product property states that any number times zero equals zero.
[tex]-3(x^2+56)=0[/tex]
Solve, use inverse operations,
[tex]x^2+56=0[/tex]
[tex]x^2=-56[/tex]
One cannot take the square root of a negative number and get a real result, thus the result is an imaginary number.
[tex]x=\sqrt{-56}[/tex]
Simplify, remove whole factors from under the radical,
[tex]x=+-2i\sqrt{14}[/tex]
