Solve the Equation by Making an Appropriate Substitution $x ^ { 4 } - 14 x ^ { 2 } + 45 = 0$

Multiple Choice

Solve the equation by making an appropriate substitution.
- $x ^ { 4 } - 14 x ^ { 2 } + 45 = 0$

A) $\{ - 3,3 , - \sqrt { 5 } , \sqrt { 5 } \}$
B) $\{ - 3,3 , - \mathrm { i } \sqrt { 5 } , \mathrm { i } \sqrt { 5 } \}$
C) $\{ 9,5 \}$
D) $\{ 3 , \sqrt { 5 } \}$